misc. stick

Deliberate Practice
When you see stellar per for mances by an expert in any
fi eld— a pianist, chess player, golfer— perhaps you marvel at
what natural talent must underlie their abilities, but expert
per for mance does not usually rise out of some ge ne tic predisposition
or IQ advantage. It rises from thousands of hours of
what Anders Ericsson calls sustained deliberate practice. If
doing something repeatedly might be considered practice, deliberate
practice is a different animal: it’s goal directed, often
solitary, and consists of repeated striving to reach beyond
your current level of per for mance. What ever the fi eld, expert
per for mance is thought to be garnered through the slow acquisition
of a larger number of increasingly complex patterns, patterns
that are used to store knowledge about which actions
to take in a vast vocabulary of different situations. Witness a
champion chess player. In studying the positions on a board, he
can contemplate many alternative moves and the countless different
directions each might precipitate. The striving, failure,
problem solving, and renewed attempts that characterize
Make It Stick ê 184
deliberate practice build the new knowledge, physiological
adaptations, and complex mental models required to attain
ever higher levels.
When Michelangelo fi nally completed painting over 400
life size fi gures on the ceiling of the Sistine Chapel, he is reported
to have written, “If people knew how hard I worked to
get my mastery, it wouldn’t seem so wonderful after all.” What
appeared to his admirers to have fl owed from sheer genius
had required four torturous years of work and dedication.20
Deliberate practice usually isn’t enjoyable, and for most learners
it requires a coach or trainer who can help identify areas
of per for mance that need to be improved, help focus attention
on specifi c aspects, and provide feedback to keep perception
and judgment accurate. The effort and per sis tence of
deliberate practice remodel the brain and physiology to accommodate
higher per for mance, but achieving expertise in
any fi eld is par tic u lar to the fi eld. It does not confer some kind
of advantage or head start toward gaining expertise in another
domain. A simple example of practice remodeling the
brain is the treatment of focal hand dystonia, a syndrome affecting
some guitarists and pianists whose repetitive playing
has rewired their brains to think that two fi ngers have been
fused into one. Through a series of challenging exercises,
they can be helped gradually to retrain their fi ngers to move
separately.
One reason that experts are sometimes perceived to possess
an uncanny talent is that some can observe a complex
per for mance in their fi eld and later reconstruct from memory
every aspect of that per for mance, in granular detail. Mozart
was famous for being able to reconstruct complex musical
scores after a single hearing. But this skill, Ericsson says, rises
Increase Your Abilities ê 185
not out of some sixth sense but from an expert’s superior perception
and memory within his domain, which are the result
of years of acquired skill and knowledge in that domain.
Most people who achieve expertise in a fi eld are destined to
remain average performers in the other realms of life.
Ten thousand hours or ten years of practice was the average
time the people Ericsson studied had invested to become
expert in their fi elds, and the best among them had spent the
larger percentage of those hours in solitary, deliberate practice.
The central idea here is that expert per for mance is a
product of the quantity and the quality of practice, not of gene
tic predisposition, and that becoming expert is not beyond
the reach of normally gifted people who have the motivation,
time, and discipline to pursue it.

Brain Training?
What about “brain training” games? We’ve seen a new kind
of business emerge, pitching online games and videos promising
to exercise your brain like a muscle, building your cognitive
ability. These products are largely founded on the fi ndings
of one Swiss study, reported in 2008, which was very
limited in scope and has not been replicated.14 The study
focused on improving “fl uid intelligence”: the facility for abstract
reasoning, grasping unfamiliar relationships, and solving
new kinds of problems. Fluid intelligence is one of two
kinds of intelligence that make up IQ. The other is crystallized
intelligence, the store house of knowledge we have accumulated
through the years. It’s clear that we can increase our crystallized
intelligence through effective learning and memory
strategies, but what about our fl uid intelligence?
A key determiner of fl uid intelligence is the capacity of a
person’s working memory— the number of new ideas and relationships
that a person can hold in mind while working
through a problem (especially with some amount of distraction).
The focus of the Swiss study was to give participants
tasks requiring increasingly diffi cult working memory challenges,
holding two different stimuli in mind for progressively
longer periods of distraction. One stimulus was a sequence of
Increase Your Abilities ê 177
numerals. The other was a small square of light that appeared
in varying locations on a screen. Both the numerals and the
locations of the square changed every three seconds. The task
was to decide— while viewing a sequence of changed numerals
and repositioned squares— for each combination of numeral
and square, whether it matched a combination that had
been presented n items back in the series. The number n increased
during the trials, making the challenge to working
memory progressively more arduous.
All the participants were tested on fl uid intelligence tasks
at the outset of the study. Then they were given these increasingly
diffi cult exercises of their working memory over periods
ranging up to nineteen days. At the end of the training, they
were retested for fl uid intelligence. They all performed better
than they had before the training, and those who had engaged
in the training for the longest period showed the greatest improvement.
These results showed for the fi rst time that fl uid
intelligence can be increased through training.
What’s the criticism?
The participants were few (only thirty- fi ve) and were all
recruited from a similar, highly intelligent population. Moreover,
the study focused on only one training task, so it is unclear
to what extent it might apply to other working- memory
training tasks, or whether the results are really about working
memory rather than some peculiarity of the par tic u lar training.
Finally, the durability of the improved per for mance is
unknown, and the results, as noted, have not been replicated
by other studies. The ability to replicate empirical results is
the bedrock of scientifi c theory. The website PsychFileDrawer
.org keeps a list of the top twenty psychological research studies
that the site’s users would like to see replicated, and the
Swiss study is the fi rst on the list. A recent attempt whose results
were published in 2013 failed to fi nd any improvements
Make It Stick ê 178
to fl uid intelligence as a result of replicating the exercises in
the Swiss study. Interestingly, participants in the study believed
that their mental capacities had been enhanced, a phenomenon
the authors describe as illusory. However, the authors
also acknowledge that an increased sense of self- effi cacy
can lead to greater per sis tence in solving diffi cult problems,
encouraged by the belief that training has improved one’s
abilities.15
The brain is not a muscle, so strengthening one skill does
not automatically strengthen others. Learning and memory
strategies such as retrieval practice and the building of mental
models are effective for enhancing intellectual abilities in the
material or skills practiced, but the benefi ts don’t extend to
mastery of other material or skills. Studies of the brains of experts
show enhanced myelination of the axons related to the
area of expertise but not elsewhere in the brain. Observed
myelination changes in piano virtuosos are specifi c to piano
virtuosity. But the ability to make practice a habit is generalizable.
To the extent that “brain training” improves one’s effi
cacy and self- confi dence, as the purveyors claim, the benefi ts
are more likely the fruits of better habits, such as learning how
to focus attention and persist at practice.
Richard Nisbett writes of environmental “multipliers” that
can deliver a disproportionate effect from a small ge ne tic
predisposition— the kid who is ge ne tically just a little bit more
curious becomes signifi cantly smarter if she’s in an environment
that feeds curiosity. Now stand that notion on its head.
Since it’s unlikely I’ll be raising my IQ anytime soon, are there
strategies or behaviors that can serve as cognitive “multipliers”
to amp up the per for mance of the intelligence I’ve already
Increase Your Abilities ê 179
got? Yes. Here are three: embracing a growth mindset, practicing
like an expert, and constructing memory cues.





At the root of our effectiveness is our
ability to grasp the world around us and to take the mea sure
of our own per for mance. We’re constantly making judgments
about what we know and don’t know and whether we’re capable
of handling a task or solving a problem. As we work at
something, we keep an eye on ourselves, adjusting our thinking
or actions as we progress.
Monitoring your own thinking is what psychologists call
metacognition (meta is Greek for “about”). Learning to be
accurate self- observers helps us to stay out of blind alleys,
make good decisions, and refl ect on how we might do better
next time. An important part of this skill is being sensitive to
the ways we can delude ourselves. One problem with poor
judgment is that we usually don’t know when we’ve got it.
Another problem is the sheer scope of the ways our judgment
can be led astray.1
5
Avoid Illusions of Knowing
Avoid Illusions of Knowing ê 103
In this chapter we discuss perceptual illusions, cognitive biases,
and distortions of memory that commonly mislead people.
Then we suggest techniques for keeping your judgment
squared with reality.
The consequences of poor judgment fi ll the daily papers.
During the summer of 2008, three stickup artists in Minneapolis
had a system going of phoning in large fast- food orders
and then relieving the delivery man of all the goods and cash
he carried. As a livelihood it was a model of simplicity. They
kept at it, failing to consider the wisdom of always placing
their orders from the same two cell phones and taking delivery
at the same two addresses.
David Garman, a Minneapolis cop, was working undercover
that summer. “It was getting more aggressive. At the
beginning, it was ‘maybe they had a gun,’ then all of a sudden
there were a couple of guns, and then they were hurting the
people when they were robbing them.”
It was a night in August when Garman got a call about a
large order phoned in to a Chinese restaurant. He or ga nized a
small team on short notice and prepared to pose as the delivery
guy. He pulled on a bulletproof vest, covered it with a casual
shirt, and shoved his .45 automatic into his pants. While
his colleagues staked out positions near the delivery address,
Garman picked up the food, drove there, and parked with his
brights shining on the front door. He’d cut a slit in the bottom
of the food bag and tucked a .38 inside to rest in his hand as
he carried the package. “The .38 has a covered hammer on it,
so I can shoot it in a bag. If I were to put the automatic in
there, it’d jam and I’d be screwed.”
So I walk up with the package and I say, “Hey, sir, did you
order some food?” He says, “Yup,” and I’m thinking this guy’s
really just going to pay me and I’m going to be out of here,
Make It Stick ê 104
and this is going to be the dumbest thing we’ve ever done. I’m
thinking if he hands me $40, I don’t even know how much
this food is. But he turns his head to look halfway back and
two other guys start to come up, and as they’re walking towards
me they fl ip hoods over their heads. That’s when I
know it’s game time. The fi rst guy whips a gun out of his
pocket and racks it and puts it to my head all in one motion,
saying, “Give me everything you’ve got motherfucker or I’ll
kill you.” I ended up shooting him through the bag. It was
four rounds.2
Not such a great livelihood after all. The guy was hit low
and survived, although he is a lesser man as a result. Garman
would have aimed higher if the food package hadn’t been so
heavy, and he took a lesson from the experience: he’s better
prepared for the next time, though he’d rather we didn’t describe
just how.
We like to think we’re smarter than the average doodle,
and even if we’re not, we feel affi rmed in this delusion each
year when the newest crop of Darwin Awards circulates by
email, that short list of self- infl icted fatalities caused by spectacularly
poor judgment, as in the case of the attorney in Toronto
who was demonstrating the strength of the windows in
his twenty- two- story offi ce tower by throwing his shoulder
against the glass when he broke it and fell through. The truth
is that we’re all hardwired to make errors in judgment. Good
judgment is a skill one must acquire, becoming an astute
observer of one’s own thinking and per for mance. We start at
a disadvantage for several reasons. One is that when we’re
incompetent, we tend to overestimate our competence and see
little reason to change. Another is that, as humans, we are readily
misled by illusions, cognitive biases, and the stories we construct
to explain the world around us and our place within
Avoid Illusions of Knowing ê 105
it. To become more competent, or even expert, we must learn
to recognize competence when we see it in others, become
more accurate judges of what we ourselves know and don’t
know, adopt learning strategies that get results, and fi nd objective
ways to track our progress.
Two Systems of Knowing
In his book Thinking, Fast and Slow, Daniel Kahneman describes
our two analytic systems. What he calls System 1 (or
the automatic system) is unconscious, intuitive, and immediate.
It draws on our senses and memories to size up a situation
in the blink of an eye. It’s the running back dodging tackles in
his dash for the end zone. It’s the Minneapolis cop, walking
up to a driver he’s pulled over on a chilly day, taking evasive
action even before he’s fully aware that his eye has seen a bead
of sweat run down the driver’s temple.
System 2 (the controlled system) is our slower pro cess of
conscious analysis and reasoning. It’s the part of thinking that
considers choices, makes decisions, and exerts self- control.
We also use it to train System 1 to recognize and respond to
par tic u lar situations that demand refl exive action. The running
back is using System 2 when he walks through the moves
in his playbook. The cop is using it when he practices taking a
gun from a shooter. The neurosurgeon is using it when he rehearses
his repair of the torn sinus.
System 1 is automatic and deeply infl uential, but it is susceptible
to illusion, and you depend on System 2 to help you
manage yourself: by checking your impulses, planning ahead,
identifying choices, thinking through their implications, and
staying in charge of your actions. When a guy in a restaurant
walks past a mother with an infant and the infant cries out
“Dada!” that’s System 1. When the blushing mother says,
Make It Stick ê 106
“No, dear, that’s not Dada, that’s a man,” she is acting as a
surrogate System 2, helping the infant refi ne her System 1.
System 1 is powerful because it draws on our accumulated
years of experience and our deep emotions. System 1 gives us
the survival refl ex in moments of danger, and the astonishing
deftness earned through thousands of hours of deliberate
practice in a chosen fi eld of expertise. In the interplay between
Systems 1 and 2— the topic of Malcolm Gladwell’s
book Blink—your instantaneous ability to size up a situation
plays against your capacity for skepticism and thoughtful
analysis. Of course, when System 1’s conclusions arise out of
misperception or illusion, they can steer you into trouble.
Learning when to trust your intuition and when to question it
is a big part of how you improve your competence in the
world at large and in any fi eld where you want to be expert.
It’s not just the dullards who fall victim. We all do, to varying
degrees. Pi lots, for example, are susceptible to a host of perceptual
illusions. They are trained to beware of them and to
use their instruments to know that they’re getting things right.
A frightening example with a happy ending is China Airlines
Flight 006 on a winter day in 1985. The Boeing 747 was
41,000 feet above the Pacifi c, almost ten hours into its elevenhour
fl ight from Taipei to LA, when engine number 4 lost
power. The plane began to lose airspeed. Rather than taking
manual control and descending below 30,000 feet to restart
the engine, as prescribed in the fl ight book, the crew held at
41,000 with the autopi lot engaged and attempted a restart.
Meanwhile, loss of the outboard engine gave the plane asymmetrical
thrust. The autopi lot tried to correct for this and
keep the plane level, but as the plane continued to slow it
also began to roll to the right. The captain was aware of the
Avoid Illusions of Knowing ê 107
deceleration, but not the extent to which the plane had entered
a right bank; his System 1 clue would have been his
vestibular refl ex— how the inner ear senses balance and
spatial orientation—but because of the plane’s trajectory,
he had the sensation of fl ying level. His System 2 clues would
have been a glimpse at the horizon and his instruments. Correct
procedure called for applying left rudder to help raise the
right wing, but his System 2 focus was on the airspeed indicator
and on the efforts of the fi rst offi cer and engineer to restart
the engine.
As its bank increased, the plane descended through 37,000
feet into high clouds, which obscured the horizon. The captain
switched off the autopi lot and pushed the nose down to
get more speed, but the plane had already rolled beyond 45
degrees and now turned upside down and fell into an uncontrolled
descent. The crew were confused by the situation. They
understood the plane was behaving erratically but were unaware
they had overturned and were in a dive. They could no
longer discern thrust from engines 1– 3 and concluded those
engines had quit as well. The plane’s dive was evident from
their fl ight gauges, but the angle was so unlikely the crew decided
the gauges had failed. At 11,000 feet they broke through
the clouds, astonished to see that they were roaring toward
earth. The captain and fi rst offi cer both pulled back hard on
the stick, exerting enormous forces on the plane but managing
to level off. Landing gear hung from the plane’s belly, and
they’d lost one of their hydraulic systems, but all four engines
came to life, and the captain was able to fl y on, diverting successfully
to San Francisco. An inspection revealed just how
severe their maneuver had been. Strains fi ve times the force of
gravity had bent the plane’s wings permanently upward, broken
two landing gear struts, and torn away two landing gear
doors and large parts of the rear horizontal stabilizers.
Make It Stick ê 108
“Spatial disorientation” is the aeronautical term for a
deadly combination of two elements: losing sight of the horizon
and relying on human sensory perception that doesn’t
jibe with reality but is so convincing that pi lots conclude their
cockpit instruments have failed. As Kahneman says, System 1,
the instinctual, refl exive system that detects danger and keeps
us safe, can be very hard to overrule. Flight 006’s initial incident,
the loss of an engine cruising at altitude, is not considered
an emergency, but it quickly became one as a result of
the captain’s actions. Rather than following prescribed procedure,
and rather than fully engaging his System 2 analytic resources
by monitoring all his instruments, he let himself become
preoccupied with the engine restart and with a single
fl ight indicator, airspeed. Then, when things spiraled out of
control, he trusted his senses over his gauges, in effect trying
to construct his own narrative of what was happening to the
plane.
There’s a long list of illusions to which pi lots can fall prey
(some with mordant names like “the leans,” “graveyard spin,”
and “the black hole approach”) and sites on the Internet where
you can listen to the chilling last words of pi lots struggling
and failing to understand and correct what’s gone wrong in
the sky. Spatial disorientation was deemed the probable cause
of the crash that killed Mel Carnahan, the governor of Missouri,
while being fl own through a thunderstorm one night in
October 2000, and the probable cause of the crash that killed
John F. Kennedy Jr. and his wife and her sister off the shore of
Martha’s Vineyard on a hazy night in July 1999. Fortunately,
the China Airlines incident came to a good end, but the National
Transportation Safety Board report of that incident reveals
just how quickly training and professionalism can be
hijacked by System 1 illusion, and therefore why we need to
Avoid Illusions of Knowing ê 109
cultivate a disciplined System 2, conscious analysis and reasoning,
that always keeps one eye on the fl ight instruments.3
Illusions and Memory Distortions
The fi lmmaker Errol Morris, in a series of articles on illusion
in the New York Times, quotes the social psychologist David
Dunning on humans’ penchant for “motivated reasoning,” or,
as Dunning put it, the “sheer genius people have at convincing
themselves of congenial conclusions while denying the
truth of incon ve nient ones.”4 (The British prime minister Benjamin
Disraeli once said of a po liti cal opponent that his conscience
was not his guide but his accomplice.) There are many
ways that our System 1 and System 2 judgments can be led
astray: perceptual illusions like those experienced by pi lots,
faulty narrative, distortions of memory, failure to recognize
when a new kind of problem requires a new kind of solution,
and a variety of cognitive biases to which we’re prone. We
describe a number of these hazards here, and then we offer
mea sures you can take, akin to scanning the cockpit instruments,
to help keep your thinking aligned with reality.
Our understanding of the world is shaped by a hunger for
narrative that rises out of our discomfort with ambiguity and
arbitrary events. When surprising things happen, we search
for an explanation. The urge to resolve ambiguity can be surprisingly
potent, even when the subject is inconsequential. In
a study where participants thought they were being mea sured
for reading comprehension and their ability to solve anagrams,
they were exposed to the distraction of a background phone
conversation. Some heard only one side of a conversation,
Make It Stick ê 110
and others heard both sides. The participants, not knowing
that the distraction itself was the subject of the study, tried to
ignore what they were hearing so as to stay focused on the
reading and anagram solutions. The results showed that overhearing
one side of a conversation proved more distracting
than overhearing both sides, and the content of those partial
conversations was better recalled later by the unintentional
eavesdroppers. Why was this? Presumably, those overhearing
half a conversation were strongly compelled to try to infer the
missing half in a way that made for a complete narrative. As
the authors point out, the study may help explain why we fi nd
one- sided cell phone conversations in public spaces so intrusive,
but it also reveals the ineluctable way we are drawn to
imbue the events around us with rational explanations.
The discomfort with ambiguity and arbitrariness is equally
powerful, or more so, in our need for a rational understanding
of our own lives. We strive to fi t the events of our lives
into a cohesive story that accounts for our circumstances, the
things that befall us, and the choices we make. Each of us has
a different narrative that has many threads woven into it
from our shared culture and experience of being human, as
well as many distinct threads that explain the singular events
of one’s personal past. All these experiences infl uence what
comes to mind in a current situation and the narrative through
which you make sense of it: Why nobody in my family attended
college until me. Why my father never made a fortune
in business. Why I’d never want to work in a corporation, or,
maybe, Why I would never want to work for myself. We
gravitate to the narratives that best explain our emotions. In
this way, narrative and memory become one. The memories
we or ga nize meaningfully become those that are better remembered.
Narrative provides not only meaning but also a
Avoid Illusions of Knowing ê 111
mental framework for imbuing future experiences and information
with meaning, in effect shaping new memories to fi t our
established constructs of the world and ourselves. No reader,
when asked to account for the choices made under pressure by
a novel’s protagonist, can keep her own life experience from
shading her explanation of what must have been going on in
the character’s interior world. The success of a magician or
politician, like that of a novelist, relies on the seductive powers
of narrative and on the audience’s willing suspension of disbelief.
Nowhere is this more evident than in the national po liti cal
debate, where like- minded people gather online, at community
meetings, and in the media to fi nd common purpose and expand
the story they feel best explains their sense of how the
world works and how humans and politicians should behave.
You can see how quickly personal narrative is invoked to
explain emotions when you read an article online whose author
has argued a position on almost any subject— for example,
an op- ed piece supporting the use of testing as a powerful
tool for learning. Scan the comments posted by readers: some
sing hallelujah while others can scarcely contain their umbrage,
each invoking a personal story that supports or refutes
the column’s main argument. The psychologists Larry Jacoby,
Bob Bjork, and Colleen Kelley, summing up studies on illusions
of comprehension, competence, and remembering, write
that it is nearly impossible to avoid basing one’s judgments on
subjective experience. Humans do not give greater credence
to an objective record of a past event than to their subjective
remembering of it, and we are surprisingly insensitive to the
ways our par tic u lar construals of a situation are unique to
ourselves. Thus the narrative of memory becomes central to
our intuitions regarding the judgments we make and the actions
we take.5
Make It Stick ê 112
It is a confounding paradox, then, that the changeable nature
of our memory not only can skew our perceptions but
also is essential to our ability to learn. As will be familiar to
you by now, every time we call up a memory, we make the
mind’s routes to that memory stronger, and this capacity to
strengthen, expand, and modify memory is central to how we
deepen our learning and broaden the connections to what we
know and what we can do. Memory has some similarities to
a Google search algorithm, in the sense that the more you
connect what you learn to what you already know, and the
more associations you make to a memory (for example, linking
it with a visual image, a place, or a larger story), then the
more mental cues you have through which to fi nd and retrieve
the memory again later. This capacity expands our agency:
our ability to take action and be effective in the world. At the
same time, because memory is a shape- shifter, reconciling the
competing demands of emotion, suggestions, and narrative, it
serves you well to stay open to the fallibility of your certainties:
even your most cherished memories may not represent
events in the exact way they occurred.
Memory can be distorted in many ways. People interpret a
story in light of their world knowledge, imposing order where
none had been present so as to make a more logical story.
Memory is a reconstruction. We cannot remember every aspect
of an event, so we remember those elements that have
greatest emotional signifi cance for us, and we fi ll in the gaps
with details of our own that are consistent with our narrative
but may be wrong.
People remember things that were implied but not specifi -
cally stated. The literature is full of examples. In one, many
people who read a paragraph about a troubled girl named
Helen Keller later mistakenly recalled the phrase “deaf, dumb,
and blind” as being in the text. This mistake was rarely made
Avoid Illusions of Knowing ê 113
by another group who read the same paragraph about a girl
named Carol Harris.6
Imagination infl ation refers to the tendency of people who,
when asked to imagine an event vividly, will sometimes begin
to believe, when asked about it later, that the event actually
occurred. Adults who were asked “Did you ever break a window
with your hand?” were more likely on a later life inventory
to report that they believed this event occurred during
their lifetimes. It seems that asking the question led them to
imagine the event, and the act of having imagined it had the
effect, later, of making them more likely to think it had occurred
(relative to another group who answered the question
without having previously imagined it occurring).
Hypothetical events that are imagined vividly can seat themselves
in the mind as fi rmly as memories of actual events. For
instance, when it is suspected that a child is being sexually
abused and he is interviewed and questioned about it, he may
imagine experiences that the interviewer describes and then
later come to “remember” them as having occurred.7 (Sadly,
of course, many memories of childhood sexual abuse are absolutely
true, usually ones reported soon after the occurrence.)
Another type of memory illusion is one caused by suggestion,
which may arise simply in the way a question is asked. In one
example, people watched a video of a car running a stop sign
at an intersection and colliding with another car passing
through. Those who were later asked to judge the speed of the
vehicles when they “contacted” each other gave an average
estimate of thirty- two miles per hour. Those who were asked
to judge the speed when the two vehicles “smashed” into each
Make It Stick ê 114
other estimated on average forty- one miles per hour. If the
speed limit was thirty miles per hour, asking the question the
second way rather than the fi rst could lead to the driver’s being
charged with speeding. Of course, the legal system knows
the danger of witnesses being asked “leading questions” (ones
that encourage a par tic u lar answer), but such questions are
diffi cult to avoid completely, because suggestibility can be
very subtle. After all, in the case just discussed, the two cars
did “smash together.”8
Some witnesses to crimes who are struggling to recall them
are instructed to let their minds roam freely, to generate whatever
comes to mind, even if it is a guess. However, the act of
guessing about possible events causes people to provide their
own misinformation, which, if left uncorrected, they may
later come to retrieve as memories. That is one reason why
people who have been interviewed after being hypnotized are
barred from testifying in court in almost all states and Canadian
provinces. The hypnotic interview typically encourages
people to let their thoughts roam freely and produce everything
that comes to mind, in hopes that they will retrieve information
that would not otherwise be produced. However,
this pro cess causes them to produce much erroneous information,
and studies have shown that when they are tested later,
under instructions only to tell exactly what they remember of
the actual events, their guesses made while under hypnosis
cloud their memories about what truly happened. In par tic ular,
they remember events they produced under hypnosis as
actual experiences, even under conditions (in the laboratory)
when it is known that the events in question did not occur.9
Interference from other events can distort memory. Suppose
the police interview a witness shortly after a crime, showing
Avoid Illusions of Knowing ê 115
pictures of possible suspects. Time passes, but eventually the
police nab a suspect, one whose picture had been viewed by
the witness. If the witness is now asked to view a lineup, he
may mistakenly remember one of the suspects whose photo
he saw as having been present at the crime. A particularly
vivid example of a related pro cess happened to the Australian
psychologist Donald M. Thomson. A woman in Sydney was
watching tele vi sion in midday when she heard a knock at the
door. When she answered it, she was attacked, raped, and left
unconscious. When she awoke and dialed the police, they came
to her aid, got a description of her assailant, and launched
a search. They spotted Donald Thomson walking down a
Sydney street, and he matched the description. They arrested
him on the spot. It turns out that Thomson had an airtight
alibi— at the exact time of the rape, he was being interviewed
on a live tele vi sion show. The police did not believe him and
sneered when he was being interrogated. However, the story
was true. The woman had been watching the show when she
heard the knock on the door. The description she gave the
police was apparently of the man she saw on tele vi sion, Donald
Thomson, rather than the rapist. Her System 1 reaction—
quick but sometimes mistaken— provided the wrong description,
probably due to her extreme emotional state.10
What psychologists call the curse of knowledge is our tendency
to underestimate how long it will take another person
to learn something new or perform a task that we have already
mastered. Teachers often suffer this illusion— the calculus
instructor who fi nds calculus so easy that she can no longer
place herself in the shoes of the student who is just starting
out and struggling with the subject. The curse-of-knowledge
effect is close kin to hindsight bias, or what is often called the
Make It Stick ê 116
knew- it- all- along effect, in which we view events after the fact
as having been more predictable than they were before they
occurred. Stock market pundits will confi dently announce on
the eve ning news why the stock market behaved as it did that
day, even though they could not have predicted the movements
that morning.11
Accounts that sound familiar can create the feeling of knowing
and be mistaken for true. This is one reason that po liti cal
or advertising claims that are not factual but are repeated can
gain traction with the public, particularly if they have emotional
resonance. Something you once heard that you hear
again later carries a warmth of familiarity that can be mistaken
for memory, a shred of something you once knew and
cannot quite place but are inclined to believe. In the world of
propaganda, this is called “the big lie” technique— even a big
lie told repeatedly can come to be accepted as truth.
Fluency illusions result from our tendency to mistake fl uency
with a text for mastery of its content. For example, if you read
a particularly lucid pre sen ta tion of a diffi cult concept, you can
get the idea that it is actually pretty simple and perhaps even
that you knew it all along. As discussed earlier, students who
study by rereading their texts can mistake their fl uency with a
text, gained from rereading, for possession of accessible knowledge
of the subject and consequently overestimate how well
they will do on a test.
Our memories are also subject to social infl uence and tend to
align with the memories of the people around us. If you are in
Avoid Illusions of Knowing ê 117
a group reminiscing about past experiences and someone
adds a wrong detail about the story, you will tend to incorporate
this detail into your own memory and later remember the
experience with the erroneous detail. This pro cess is called
“memory conformity” or the “social contagion of memory”:
one person’s error can “infect” another person’s memory. Of
course, social infl uences are not always bad. If someone recalls
details of joint memory on which you are somewhat hazy,
your subsequent memory will be updated and will hold a
more accurate record of the past event.12
In the obverse of the social infl uence effect, humans are predisposed
to assume that others share their beliefs, a pro cess
called the false consensus effect. We generally fail to recognize
the idiosyncratic nature of our personal understanding of the
world and interpretation of events and that ours differ from
others’. Recall how surprised you were recently, on commiserating
with a friend about the general state of affairs, to discover
that she sees in an entirely different light matters on which you
thought the correct view was fundamental and obvious: climate
change, gun control, fracking of gas wells— or perhaps
something very local, such as whether to pass a bond issue for
a school building or to oppose construction of a big box store
in the neighborhood.13
Confi dence in a memory is not a reliable indication of its accuracy.
We can have utmost faith in a vivid, nearly literal
memory of an event and yet fi nd that we actually have it all
wrong. National tragedies, like the assassination of President
John Kennedy or the events surrounding 9/11, create what
psychologists call “fl ashbulb” memories, named for the vivid
Make It Stick ê 118
images that we retain: where we were when we got the news,
how we learned it, how we felt, what we did. These memories
are thought to be indelible, burned into our minds, and it is
true that the broad outlines of such catastrophes, thoroughly
reported in the media, are well remembered, but your memory
of your personal circumstances surrounding the events
may not necessarily be accurate. There have been numerous
studies of this phenomenon, including surveys of fi fteen hundred
Americans’ memories of the September 11 attacks. In
this study, the respondents’ memories were surveyed a week
after the attacks, again a year later, and then again three years
and ten years later. Respondents’ most emotional memories
of their personal details at the time they learned of the attacks
are also those of which they are most confi dent and, paradoxically,
the ones that have most changed over the years relative
to other memories about 9/11.14
Mental Models
As we develop mastery in the various areas of our lives, we
tend to bundle together the incremental steps that are required
to solve different kinds of problems. To use an analogy from
a previous chapter, you could think of them as something
like smart- phone apps in the brain. We call them mental models.
Two examples in police work are the choreography of the
routine traffi c stop and the moves to take a weapon from an
assailant at close quarters. Each of these maneuvers involves a
set of perceptions and actions that cops can adapt with little
conscious thought in response to context and situation. For a
barista, a mental model would be the steps and ingredients to
produce a perfect sixteen- ounce decaf frappuccino. For the
receptionist at urgent care, it’s triage and registration.
Avoid Illusions of Knowing ê 119
The better you know something, the more diffi cult it becomes
to teach it. So says physicist and educator Eric Mazur
of Harvard. Why? As you get more expert in complex areas,
your models in those areas grow more complex, and the component
steps that compose them fade into the background of
memory (the curse of knowledge). A physicist, for example,
will create a mental library of the principles of physics she can
use to solve the various kinds of problems she encounters in
her work: Newton’s laws of motion, for example, or the laws
of conservation of momentum. She will tend to sort problems
based on their underlying principles, whereas a novice will
group them by similarity of surface features, like the apparatus
being manipulated in the problem (pulley, inclined plane,
etc.). One day, when she goes to teach an intro physics class,
she explains how a par tic u lar problem calls for something
from Newtonian mechanics, forgetting that her students have
yet to master the underlying steps she has long ago bundled
into one unifi ed mental model. This presumption by the professor
that her students will readily follow something complex
that appears fundamental in her own mind is a metacognitive
error, a misjudgment of the matchup between what
she knows and what her students know. Mazur says that the
person who knows best what a student is struggling with in
assimilating new concepts is not the professor, it’s another
student.15 This problem is illustrated through a very simple
experiment in which one person plays a common tune inside
her head and taps the rhythm with her knuckles and another
person hearing the rhythmic taps must guess the tune. Each
tune comes from a fi xed set of twenty- fi ve, so the statistical
chance of guessing it is 4 percent. Tellingly, the participants
who have the tune in mind estimate that the other person will
guess correctly 50 percent of the time, but in fact the listeners
Make It Stick ê 120
guess correctly only 2.5 percent of the time, no better than
chance.16
Like Coach Dooley’s football players memorizing their playbooks,
we all build mental libraries of myriad useful solutions
that we can call on at will to help us work our way from one
Saturday game to the next. But we can be tripped by these
models, too, when we fail to recognize a new problem that
appears to be a familiar one is actually something quite different
and we pull out a solution to address it that doesn’t work
or makes things worse. The failure to recognize when your
solution doesn’t fi t the problem is another form of faulty selfobservation
that can lead you into trouble.
Mike Ebersold, the neurosurgeon, was called into the operating
room one day to help a surgical resident who, in the
midst of removing a brain tumor, was losing the patient. The
usual model for cutting out a tumor calls for taking your time,
working carefully around the growth, getting a clean margin,
saving the surrounding nerves. But when the growth is in the
brain, and if you get bleeding behind it, pressure on the brain
can turn fatal. Instead of slow- and- careful, you need just the
opposite, cutting the growth out very quickly so the blood
can drain, and then working to repair the bleeding. “Initially
you might be a little timid to take the big step,” Mike says. “It’s
not pretty, but the patient’s survival depends on your knowing
to switch gears and do it fast.” Mike assisted, and the surgery
was successful.
Like the infant who calls the stranger Dada, we must cultivate
the ability to discern when our mental models aren’t
working: when a situation that seems familiar is actually different
and requires that we reach for a different solution and
do something new.
Avoid Illusions of Knowing ê 121
Unskilled and Unaware of It
Incompetent people lack the skills to improve because they are
unable to distinguish between incompetence and competence.
This phenomenon, of par tic u lar interest for metacognition,
has been named the Dunning- Kruger effect after the psychologists
David Dunning and Justin Kruger. Their research showed
that incompetent people overestimate their own competence
and, failing to sense a mismatch between their per for mance
and what is desirable, see no need to try to improve. (The title of
their initial paper on the topic was “Unskilled and Unaware
of It.”) Dunning and Kruger have also shown that incompetent
people can be taught to raise their competence by learning
the skills to judge their own per for mance more accurately, in
short, to make their metacognition more accurate. In one series
of studies that demonstrate this fi nding, they gave students
a test of logic and asked them to rate their own per for mance. In
the fi rst experiment the results confi rmed expectations that the
least competent students were the most out of touch with their
per for mance: students who scored at the twelfth percentile on
average believed that their general logical reasoning ability fell
at the sixty- eighth percentile.
In a second experiment, after taking an initial test and rating
their own per for mance, the students were shown the other
students’ answers and then their own answers and asked to
reestimate the number of test questions they had answered
correctly. The students whose per for mance was in the bottom
quartile failed to judge their own per for mance more accurately
after seeing the more competent choices of their peers
and in fact tended to raise their already infl ated estimates of
their own ability.
A third experiment explored whether poor performers could
learn to improve their judgment. The students were given ten
Make It Stick ê 122
problems in logical reasoning and after the test were asked to
rate their logical reasoning skills and test per for mance. Once
again, the students in the bottom quartile grossly overestimated
their per for mance. Next, half the students received
ten minutes of training in logic (how to test the accuracy of a
syllogism); the other half of the students were given an unrelated
task. All the students were then asked to estimate again
how well they had performed on the test. Now the students in
the bottom quartile who had received the training were much
more accurate estimators of the number of questions they got
right and of how they performed compared to the other students.
Those in the bottom quartile who didn’t receive the
training held to their mistaken conviction that they had performed
well.
How is it that incompetent people fail to learn through
experience that they are unskilled? Dunning and Kruger offer
several theories. One is that people seldom receive negative
feedback about their skills and abilities from others in everyday
life, because people don’t like to deliver the bad news.
Even if people get negative feedback, they must come to an
accurate understanding of why the failure occurred. For success
everything must go right, but by contrast, failure can be
attributed to any number of external causes: it’s easy to blame
the tool for what the hand cannot do. Finally, Dunning and
Kruger suggest that some people are just not astute at reading
how other people are performing and are therefore less able
to spot competence when they see it, making them less able to
make comparative judgments of their own per for mance.
These effects are more likely to occur in some contexts and
with some skills than with others. In some domains, the revelation
of one’s incompetence can be brutally frank. The authors
can all remember from their childhoods when a teacher
would appoint two boys to pick other kids for softball teams.
Avoid Illusions of Knowing ê 123
The good players are picked fi rst, the worst last. You learn
your peers’ judgments of your softball abilities in a very public
manner, so it would be hard for the last- picked player to
think “I must be really good at softball.” However, most
realms of life do not render such stark judgments of ability.17
To sum up, the means by which we navigate the world—
Daniel Kahneman’s Systems 1 and 2— rely on our perceptual
systems, intuition, memory, and cognition, with all their tics,
warts, biases, and fl aws. Each of us is an astounding bundle of
perceptual and cognitive abilities, coexisting with the seeds of
our own undoing. When it comes to learning, what we choose
to do is guided by our judgments of what works and what
doesn’t, and we are easily misled.
Our susceptibility to illusion and misjudgment should give
us all pause, and especially so to the advocates of “studentdirected
learning,” a theory now current among some parents
and educators. This theory holds that students know best what
they need to study to master a subject, and what pace and
methods work best for them. For example, at Manhattan Free
School in East Harlem, opened in 2008, students “do not receive
grades, take tests or have to do anything they do not feel
like doing.” The Brooklyn Free School, which opened in 2004,
along with a new crop of homeschooling families who call
themselves “unschoolers,” follows the precept that what ever
intrigues the learner is what will result in the best learning. 18
The intent is laudatory. We know that students need to take
more control of their own learning by employing strategies
like those we have discussed. For example, they need to test
themselves, both to attain the direct benefi ts of increased retention
and to determine what they know and don’t know to
more accurately judge their progress and focus on material
Make It Stick ê 124
that needs more work. But few students practice these strategies,
and those who do will need more than encouragement if
they are to practice them effectively: It turns out that even
when students understand that retrieval practice is a superior
strategy, they often fail to persist long enough to get the lasting
benefi t. For example, when students are presented with a
body of material to master, say a stack of foreign vocabulary
fl ashcards, and are free to decide when to drop a card out of
the deck because they’ve learned it, most students drop the
card when they’ve gotten it right once or twice, far sooner
than they should. The paradox is that those students who
employ the least effective study strategies overestimate their
learning the most and, as a consequence of their misplaced
confi dence, they are not inclined to change their habits.
The football player preparing for next Saturday’s game
doesn’t leave his per for mance to intuition, he runs through his
plays and mixes it up to discover the rough edges and work
them out on the fi eld well before suiting up for the big game.
If this kind of behavior were anywhere close to the norm for
students in their academics today, then self- directed learning
would be highly effective. But of course the football player is
not self- directed, his practice is guided by a coach. Likewise,
most students will learn academics better under an instructor
who knows where improvement is needed and structures the
practice required to achieve it.19
The answer to illusion and misjudgment is to replace subjective
experience as the basis for decisions with a set of objective
gauges outside ourselves, so that our judgment squares
with the real world around us. When we have reliable reference
points, like cockpit instruments, and make a habit of
checking them, we can make good decisions about where to
focus our efforts, recognize when we’ve lost our bearings, and
fi nd our way back again. Here are some examples.
Avoid Illusions of Knowing ê 125
Tools and Habits for Calibrating
Your Judgment
Most important is to make frequent use of testing and retrieval
practice to verify what you really do know versus what
you think you know. Frequent low- stakes quizzes in class help
the instructor verify that students are in fact learning as well
as they appear to be and reveal the areas where extra attention
is needed. Doing cumulative quizzing, as Andy Sobel
does in his po liti cal economics course, is especially powerful
for consolidating learning and knitting the concepts from one
stage of a course into new material encountered later. As a
learner, you can use any number of practice techniques to selftest
your mastery, from answering fl ashcards to explaining
key concepts in your own words, and to peer instruction (see
below).
Don’t make the mistake of dropping material from your
testing regime once you’ve gotten it correct a couple of times.
If it’s important, it needs to be practiced, and practiced again.
And don’t put stock in momentary gains that result from
massed practice. Space your testing, vary your practice, keep
the long view.
Peer instruction, a learning model developed by Eric Mazur,
incorporates many of the foregoing principles. The material
to be covered in class is assigned for reading beforehand. In
class, the lecture is interspersed with quick tests that present
students with a conceptual question and give them a minute
or two to grapple with it; they then try, in small groups, to
reach a consensus on the correct answer. In Mazur’s experience,
this pro cess engages the students in the underlying concepts
of the lecture material; reveals students’ problems in
Make It Stick ê 126
reaching understanding; and provides opportunities for them
to explain their understanding, receive feedback, and assess
their learning compared to other students. Likewise, the process
serves as a gauge for the instructor of how well the students
are assimilating the material and in what areas more or
less work is needed. Mazur tries to pair students who initially
had different answers to a question so that they can see another
point of view and try to convince one another of who is
right.
For two more examples of this technique, see the profi
les of the professors Mary Pat Wenderoth and Michael
D. Matthews in Chapter 8.20
Pay attention to the cues you’re using to judge what you have
learned. Whether something feels familiar or fl uent is not always
a reliable indicator of learning. Neither is your level of
ease in retrieving a fact or a phrase on a quiz shortly after
encountering it in a lecture or text. (Ease of retrieval after a
delay, however, is a good indicator of learning.) Far better is
to create a mental model of the material that integrates the
various ideas across a text, connects them to what you already
know, and enables you to draw inferences. How ably
you can explain a text is an excellent cue for judging comprehension,
because you must recall the salient points from
memory, put them into your own words, and explain why
they are signifi cant— how they relate to the larger subject.
Instructors should give corrective feedback, and learners
should seek it. In his interview with Errol Morris, the psychologist
David Dunning argues that the path to self- insight
leads through other people. “So it really depends on what sort
Avoid Illusions of Knowing ê 127
of feedback you are getting. Is the world telling you good
things? Is the world rewarding you in a way that you would
expect a competent person to be rewarded? If you watch
other people, you often fi nd there are different ways to do
things; there are better ways to do things. ‘I’m not as good as
I thought I was, but I have something to work on.’ ” Think of
the kids lining up to join the softball team— would you be
picked?21
In many fi elds, the practice of peer review serves as an external
gauge, providing feedback on one’s per for mance. Most
medical practice groups have morbidity/mortality conferences,
and if a doctor has a bad patient outcome, it will be
presented there. The other doctors will pick it apart, or say
“You did a good job, it was just a bad situation.” Mike Ebersold
argues that people in his fi eld should practice as a part of
a group. “If there are other neurosurgeons around you, it’s a
safeguard. If you’re doing something that’s not acceptable,
they’ll call you to task for it.”
In many settings, your judgment and learning are calibrated
by working alongside a more experienced partner: airline fi rst
offi cers with captains, rookies with seasoned cops, residents
with experienced surgeons. The apprentice model is a very old
one in human experience, as novices (whether cobblers or attorneys)
have traditionally learned their craft from experienced
practitioners.
In other settings, teams are formed of people with complementary
areas of expertise. When doctors implant medical
devices like pacemakers and neural stimulators of the type
that treat incontinence or the symptoms of Parkinson’s disease,
the manufacturer has a product representative right in
the operating room with the surgeon. The rep has seen many
Make It Stick ê 128
surgeries using the device, knows the kinds of patients that
will benefi t from it, knows the contraindications and adverse
events, and has a hotline to the engineers and clinicians on the
company’s staff. The rep tracks the surgery to make sure the
device is implanted in the correct position, the leads are inserted
to the correct depth, and so on. Every part of the team
benefi ts. The patient is assured of an appropriate and successful
surgery. The doctor gets product and troubleshooting expertise
at her fi ngertips. And the company makes sure its
products are used correctly.
Training that simulates the kinds of demands and changeable
conditions that can be expected in real- world settings helps
learners and trainers assess mastery and focus on areas where
understanding or competency need to be raised. Take police
work, where many different forms of simulation are used in
training. For fi rearms training it’s often video- based scenarios,
with a large screen set up at one end of a room where a number
of props have been placed to imitate the situation confronting
the offi cer, who enters the scene armed with a gun
that has been modifi ed to interact with the video.
Lieutenant Catherine Johnson of the Minneapolis Police
Department describes a couple of such simulations in which
she has trained:
One was a traffi c stop. The training room had the screen at
one end and objects around the room— a big blue mailbox, a
fi re hydrant, a doorway— that you could use for cover in dealing
with what was happening on the screen. I remember walking
toward the screen, and the video simulating my coming up
to the car as I did that, very realistic, and suddenly the trunk
popped up and a guy with a shotgun rose out and shot me.
Avoid Illusions of Knowing ê 129
Which, to this day, every time I go up to a car on a traffi c stop,
I push down hard on the trunk to make sure it isn’t open. And
it’s because of that one scenario in the training that I went
through.
Another fi rearm simulation was a domestic call, and it starts
where I am approaching the residence and there’s a guy on his
porch. The instant I show up I see that he has a gun in his
hand. I order him to drop it, and the fi rst thing he does is turn
and start walking away. And my thinking at that point is that I
can’t shoot this guy in the back, and there’s nobody over there
that looks to be in danger, so what am I going to do? In the
time it takes me to pro cess whether or not I should shoot this
guy, he’s already turned around and shot me. Because my reaction
was slower than his action. Action beats reaction every
time. That’s one mantra that’s drilled into our minds.22
The fi rearms simulations can play out in a variety of ways
both deadly and peaceful. There’s not so much a right or
wrong answer to the situation as there is a complex set of factors,
some of which, like whether the individual on the porch
has a criminal history, may be known to the offi cer when she
enters the scene. At the conclusion, the offi cer debriefs with
her trainer, getting feedback. The exercise isn’t all about technique,
it’s about clear thinking and appropriate refl exes—
visual and verbal clues to watch for, possible outcomes, being
clear about the appropriate use of deadly force, and fi nding
the words after the fact that will account for actions you have
taken in the urgency of the moment.
Simulation is not perfect. Johnson recounts how offi cers
are trained to take a gun from an assailant at close quarters, a
maneuver they practice by role- playing with a fellow offi cer.
It requires speed and deftness: striking an assailant’s wrist with
one hand to break his grip while simultaneously wresting the
Make It Stick ê 130
gun free with the other. It’s a move that offi cers had been in the
habit of honing through repetition, taking the gun, handing it
back, taking it again. Until one of their offi cers, on a call in
the fi eld, took the gun from an assailant and handed it right
back again. In their mutual astonishment, the offi cer managed
to reseize the gun and hang onto it. The training regime had
violated the cardinal rule that you should practice like you
play, because you will play like you practice.
Sometimes the most powerful feedback for calibrating your
sense of what you do and don’t know are the mistakes you
make in the fi eld, assuming you survive them and are receptive
to the lesson.23



How Learning Occurs
To help you understand how diffi culty can be desirable, we’ll
briefl y describe here how learning occurs.
Encoding
Let’s imagine you’re Mia, standing in a gravel pit watching a
jump instructor explain and demonstrate the parachute landing
fall. The brain converts your perceptions into chemical
and electrical changes that form a mental repre sen ta tion of
the patterns you’ve observed. This pro cess of converting sensory
perceptions into meaningful repre sen ta tions in the brain
is still not perfectly understood. We call the pro cess encoding,
and we call the new repre sen ta tions within the brain memory
traces. Think of notes jotted or sketched on a scratchpad, our
short- term memory.
Much of how we run our day- to- day lives is guided by the
ephemera that clutter our short- term memory and are, fortunately,
soon forgotten— how to jigger the broken latch on the
Embrace Difficulties ê 73
locker you used when you suited up at the gym today; remembering
to stop for an oil change after your workout. But
the experiences and learning that we want to salt away for the
future must be made stronger and more durable— in Mia’s
case, the distinctive moves that will enable her to hit the ground
without breaking an ankle, or worse.3
Consolidation
The pro cess of strengthening these mental repre sen ta tions for
long- term memory is called consolidation. New learning is
labile: its meaning is not fully formed and therefore is easily
altered. In consolidation, the brain reorganizes and stabilizes
the memory traces. This may occur over several hours or longer
and involves deep pro cessing of the new material, during
which scientists believe that the brain replays or rehearses the
learning, giving it meaning, fi lling in blank spots, and making
connections to past experiences and to other knowledge already
stored in long- term memory. Prior knowledge is a prerequisite
for making sense of new learning, and forming those
connections is an important task of consolidation. Mia’s considerable
athletic skills, physical self- awareness, and prior experience
represent a large body of knowledge to which the
elements of a successful PLF would fi nd many connections. As
we’ve noted, sleep seems to help memory consolidation, but
in any case, consolidation and transition of learning to longterm
storage occurs over a period of time.
An apt analogy for how the brain consolidates new learning
may be the experience of composing an essay. The fi rst
draft is rangy, imprecise. You discover what you want to say
by trying to write it. After a couple of revisions you have sharpened
the piece and cut away some of the extraneous points.
You put it aside to let it ferment. When you pick it up again
Make It Stick ê 74
a day or two later, what you want to say has become clearer
in your mind. Perhaps you now perceive that there are three
main points you are making. You connect them to examples
and supporting information familiar to your audience. You
rearrange and draw together the elements of your argument
to make it more effective and elegant.
Similarly, the pro cess of learning something often starts out
feeling disor ga nized and unwieldy; the most important aspects
are not always salient. Consolidation helps or ga nize and solidify
learning, and, notably, so does retrieval after a lapse of some
time, because the act of retrieving a memory from long- term
storage can both strengthen the memory traces and at the same
time make them modifi able again, enabling them, for example,
to connect to more recent learning. This pro cess is called reconsolidation.
This is how retrieval practice modifi es and strengthens
learning.
Suppose that on day 2 of jump school, you’re put on the
spot to execute your parachute landing fall and you struggle
to recall the correct posture and compose yourself— feet and
knees together, knees slightly bent, eyes on the horizon— but
in the refl ex to break your fall you throw your arm out, forgetting
to pull your elbows tight to your sides. You could have
broken the arm or dislocated your shoulder if this were the
real deal. This effort to reconstruct what you learned the day
before is ragged, but in making it, critical elements of the maneuver
come clearer and are reconsolidated for stronger memory.
If you’re practicing something over and over in rapid- fi re
fashion, whether it’s your parachute landing fall or the conjugation
of foreign verbs, you’re leaning on short- term memory,
and very little mental effort is required. You show gratifying
improvement rather quickly, but you haven’t done much to
strengthen the underlying repre sen ta tion of those skills. Your
per for mance in the moment is not an indication of durable
Embrace Difficulties ê 75
learning. On the other hand, when you let the memory recede
a little, for example by spacing or interleaving the practice,
retrieval is harder, your per for mance is less accomplished, and
you feel let down, but your learning is deeper and you will
retrieve it more easily in the future.4
Retrieval
Learning, remembering, and forgetting work together in interesting
ways. Durable, robust learning requires that we do
two things. First, as we recode and consolidate new material
from short- term memory into long- term memory, we must
anchor it there securely. Second, we must associate the material
with a diverse set of cues that will make us adept at recalling
the knowledge later. Having effective retrieval cues is an
aspect of learning that often goes overlooked. The task is
more than committing knowledge to memory. Being able to
retrieve it when we need it is just as important.
The reason we don’t remember how to tie knots even after
we’ve been taught is because we don’t practice and apply
what we’ve learned. Say you’re in the city park one day and
come across an Ea gle Scout teaching knots. On a whim you
take an hour’s lesson. He demonstrates eight or ten specimens,
explains what each is useful for, has you practice tying them,
and sends you away with a short length of rope and a cheat
sheet. You head home committed to learning these knots, but
life is full, and you fail to practice them. They are soon forgotten,
and this story could end there, with no learning. But then,
as it happens, the following spring you buy a small fi shing
boat, and you want to attach an anchor on a line. With rope
in hand and feeling mildly stumped, you recall from your lesson
that there was a knot for putting a loop in the end of a
line. You are now practicing retrieval. You fi nd your cheat
Make It Stick ê 76
sheet and relearn how to tie a bowline. You put a small loop
in the rope and then take the short end and draw it through,
silently reciting the little memory device you were given: the
rabbit comes up from his hole, goes around the tree, and goes
back down. Retrieval again. A little snugging- up, and there
you have your knot, a dandy piece of scoutcraft of the kind
you’d always fancied knowing. Later, you put a piece of rope
beside the chair where you watch TV and practice the bowline
during commercials. You are doing spaced practice. Over
the coming weeks you’re surprised at how many little jobs are
easier if you have a piece of rope with a loop in the end. More
spaced practice. By August you have discovered every possible
use and purpose in your life for the bowline knot.
Knowledge, skills, and experiences that are vivid and hold
signifi cance, and those that are periodically practiced, stay with
us. If you know you’re soon to throw yourself out of a troop
transport, you listen up good when they’re telling you when
and how to pull the rip cord on your reserve chute, or what
can go wrong at twelve hundred feet and how to “just sort of
swim out of it.” The mental rehearsal you conduct while lying
in your bunk too tired to sleep and wishing the next day was
already over and well- jumped is a form of spaced practice,
and that helps you, too.
Extending Learning: Updating Retrieval Cues
There’s virtually no limit to how much learning we can remember
as long as we relate it to what we already know. In
fact, because new learning depends on prior learning, the more
we learn, the more possible connections we create for further
learning. Our retrieval capacity, though, is severely limited.
Most of what we’ve learned is not accessible to us at any given
moment. This limitation on retrieval is helpful to us: if every
Embrace Difficulties ê 77
memory were always readily to hand, you would have a hard
time sorting through the sheer volume of material to put your
fi nger on the knowledge you need at the moment: where did
I put my hat, how do I sync my electronic devices, what goes
into a perfect brandy Manhattan?
Knowledge is more durable if it’s deeply entrenched, meaning
that you have fi rmly and thoroughly comprehended a
concept, it has practical importance or keen emotional weight
in your life, and it is connected with other knowledge that
you hold in memory. How readily you can recall knowledge
from your internal archives is determined by context, by recent
use, and by the number and vividness of cues that you have
linked to the knowledge and can call on to help bring it forth.5
Here’s the tricky part. As you go through life, you often
need to forget cues associated with older, competing memories
so as to associate them successfully with new ones. To
learn Italian in middle age, you may have to forget your high
school French, because every time you think “to be” and hope
to come up with the Italian essere, up pops etre, despite your
most earnest intentions. Traveling in En gland, you have to
suppress your cues to drive on the right side of the road so
you can establish reliable cues to stay on the left. Knowledge
that is well entrenched, like real fl uency in French or years of
experience driving on the right side of the road, is easily relearned
later, after a period of disuse or after being interrupted
by competition for retrieval cues. It’s not the knowledge itself
that has been forgotten, but the cues that enable you to fi nd
and retrieve it. The cues for the new learning, driving on the
left, displace those for the old, driving on the right (if we are
lucky).
The paradox is that some forgetting is often essential for
new learning.6 When you change from a PC to a Mac, or from
one Windows platform to another, you have to do enormous
Make It Stick ê 78
forgetting in order to learn the architecture of the new system
and become adept at manipulating it so readily that your attention
can focus on doing your work and not on working the
machine. Jump school training provides another example:
After their military ser vice, many paratroopers take an interest
in smoke jumping. Smokejumpers use different airplanes,
different equipment, and different jump protocols. Having
trained at the army’s jump school is cited as a distinct disadvantage
for smoke jumping, because you have to unlearn one
set of procedures that you have practiced to the point of refl
ex and replace them with another. Even in cases where both
bodies of learning seem so similar to the uninitiated— jumping
out of an airplane with a parachute on your back— you may
have to forget the cues to a complex body of learning that you
possess if you are to acquire a new one.
We know this problem of reassigning cues to memory from
our own lives, even on the simplest levels. When our friend
Jack fi rst takes up with Joan, we sometimes call the couple
“Jack and Jill,” as the cue “Jack and” pulls up the old nursery
rhyme that’s so thoroughly embedded in memory. About the
time we have “Jack and” reliably cuing “Joan,” alas, Joan
throws him over, and he takes up with Jenny. Good grief!
Half of the time that we mean to say Jack and Jenny we catch
ourselves saying Jack and Joan. It would have been easier had
Jack picked up with Katie, so that the trailing K sound in his
name handed us off to the initiating K in hers, but no such
luck. Alliteration can be a handy cue, or a subversive one. In
all of this turmoil you don’t forget Jill, Joan, or Jenny, but you
“repurpose” your cues so that you can keep pace with the
changing opera of Jack’s life.7
It is a critical point that as you learn new things, you don’t
lose from long- term memory most of what you have learned
well in life; rather, through disuse or the reassignment of cues,
Embrace Difficulties ê 79
you forget it in the sense that you’re unable to call it up easily.
For example, if you’ve moved several times, you may not be
able to recall a previous address from twenty years ago. But if
you are given a multiple choice test for the address, you can
probably pick it out easily, for it still abides, as it were, in the
uncleaned closet of your mind. If you have ever immersed
yourself in writing stories of your past, picturing the people
and places of earlier days, you may have been surprised by the
memories that started fl ooding back, things long forgotten
now coming to mind. Context can unleash memories, as when
the right key works to open an old lock. In Marcel Proust’s
Remembrance of Things Past, the narrator grieves over his
inability to recall the days of his adolescence in the French
village of his aunt and uncle, until one day the taste of a cake
dipped in lime blossom tea brings it all rushing back, all the
people and events he thought had long since been lost to time.
Most people have experiences like Proust’s when a sight or
sound or smell brings back a memory in full force, even some
episode you have not thought about in years.8
Easier Isn’t Better
Psychologists have uncovered a curious inverse relationship
between the ease of retrieval practice and the power of that
practice to entrench learning: the easier knowledge or a skill
is for you to retrieve, the less your retrieval practice will benefi
t your retention of it. Conversely, the more effort you have
to expend to retrieve knowledge or skill, the more the practice
of retrieval will entrench it.
Not long ago the California Polytechnic State University
baseball team, in San Luis Obispo, became involved in an interesting
experiment in improving their batting skills. They were
all highly experienced players, adept at making solid contact
Make It Stick ê 80
with the ball, but they agreed to take extra batting practice
twice a week, following two different practice regimens, to
see which type of practice produced better results.
Hitting a baseball is one of the hardest skills in sports. It
takes less than half a second for a ball to reach home plate. In
this instant, the batter must execute a complex combination
of perceptual, cognitive, and motor skills: determining the
type of pitch, anticipating how the ball will move, and aiming
and timing the swing to arrive at the same place and moment
as the ball. This chain of perceptions and responses must be so
deeply entrenched as to become automatic, because the ball is
in the catcher’s mitt long before you can even begin to think
your way through how to connect with it.
Part of the Cal Poly team practiced in the standard way.
They practiced hitting forty- fi ve pitches, evenly divided into
three sets. Each set consisted of one type of pitch thrown
fi fteen times. For example, the fi rst set would be fi fteen fastballs,
the second set fi fteen curveballs, and the third set fi fteen
changeups. This was a form of massed practice. For each
set of 15 pitches, as the batter saw more of that type, he got
gratifyingly better at anticipating the balls, timing his swings,
and connecting. Learning seemed easy.
The rest of the team were given a more diffi cult practice
regimen: the three types of pitches were randomly interspersed
across the block of forty- fi ve throws. For each pitch, the batter
had no idea which type to expect. At the end of the fortyfi
ve swings, he was still struggling somewhat to connect with
the ball. These players didn’t seem to be developing the profi -
ciency their teammates were showing. The interleaving and
spacing of different pitches made learning more arduous and
feel slower.
The extra practice sessions continued twice weekly for six
weeks. At the end, when the players’ hitting was assessed, the
Embrace Difficulties ê 81
two groups had clearly benefi ted differently from the extra
practice, and not in the way the players expected. Those who
had practiced on the randomly interspersed pitches now
displayed markedly better hitting relative to those who had
practiced on one type of pitch thrown over and over. These
results are all the more interesting when you consider that
these players were already skilled hitters prior to the extra
training. Bringing their per for mance to an even higher level is
good evidence of a training regimen’s effectiveness.
Here again we see the two familiar lessons. First, that some
diffi culties that require more effort and slow down apparent
gains— like spacing, interleaving, and mixing up practice—
will feel less productive at the time but will more than compensate
for that by making the learning stronger, precise, and
enduring. Second, that our judgments of what learning strategies
work best for us are often mistaken, colored by illusions
of mastery.
When the baseball players at Cal Poly practiced curveball
after curveball over fi fteen pitches, it became easier for them to
remember the perceptions and responses they needed for that
type of pitch: the look of the ball’s spin, how the ball changed
direction, how fast its direction changed, and how long to wait
for it to curve. Per for mance improved, but the growing ease of
recalling these perceptions and responses led to little durable
learning. It is one skill to hit a curveball when you know a
curveball will be thrown; it is a different skill to hit a curveball
when you don’t know it’s coming. Baseball players need to
build the latter skill, but they often practice the former, which,
being a form of massed practice, builds per for mance gains on
short- term memory. It was more challenging for the Cal Poly
batters to retrieve the necessary skills when practice involved
random pitches. Meeting that challenge made the per for mance
gains painfully slow but also long lasting.
Make It Stick ê 82
This paradox is at the heart of the concept of desirable
diffi culties in learning: the more effort required to retrieve
(or, in effect, relearn) something, the better you learn it. In
other words, the more you’ve forgotten about a topic, the
more effective relearning will be in shaping your permanent
knowledge.9
How Effort Helps
Reconsolidating Memory
Effortful recall of learning, as happens in spaced practice, requires
that you “reload” or reconstruct the components of the
skill or material anew from long- term memory rather than
mindlessly repeating them from short- term memory.10 During
this focused, effortful recall, the learning is made pliable again:
the most salient aspects of it become clearer, and the consequent
reconsolidation helps to reinforce meaning, strengthen
connections to prior knowledge, bolster the cues and retrieval
routes for recalling it later, and weaken competing routes.
Spaced practice, which allows some forgetting to occur between
sessions, strengthens both the learning and the cues
and routes for fast retrieval when that learning is needed
again, as when the pitcher tries to surprise the batter with a
curveball after pitching several fastballs. The more effort that
is required to recall a memory or to execute a skill, provided
that the effort succeeds, the more the act of recalling or executing
benefi ts the learning.11
Massed practice gives us the warm sensation of mastery
because we’re looping information through short- term memory
without having to reconstruct the learning from longterm
memory. But just as with rereading as a study strategy,
the fl uency gained through massed practice is transitory, and
our sense of mastery is illusory. It’s the effortful pro cess of
Embrace Difficulties ê 83
reconstructing the knowledge that triggers reconsolidation
and deeper learning.
Creating Mental Models
With enough effortful practice, a complex set of interrelated
ideas or a sequence of motor skills fuse into a meaningful
whole, forming a mental model somewhat akin to a “brain
app”. Learning to drive a car involves a host of simultaneous
actions that require all of our powers of concentration and
dexterity while we are learning them. But over time, these
combinations of cognition and motor skills— for example,
the perceptions and maneuvers required to parallel park or
manipulate a stick shift— become ingrained as sets of mental
models associated with driving. Mental models are forms of
deeply entrenched and highly effi cient skills (seeing and unloading
on a curveball) or knowledge structures (a memorized
sequence of chess moves) that, like habits, can be adapted
and applied in varied circumstances. Expert per for mance is
built through thousands of hours of practice in your area of
expertise, in varying conditions, through which you accumulate
a vast library of such mental models that enables you to
correctly discern a given situation and instantaneously select
and execute the correct response.
Broadening Mastery
Retrieval practice that you perform at different times and in
different contexts and that interleaves different learning material
has the benefi t of linking new associations to the material.
This pro cess builds interconnected networks of knowledge
that bolster and support mastery of your fi eld. It also
multiplies the cues for retrieving the knowledge, increasing
the versatility with which you can later apply it.
Make It Stick ê 84
Think of an experienced chef who has internalized the
complex knowledge of how fl avors and textures interact; how
ingredients change form under heat; the differing effects to be
achieved with a saucepan versus a wok, with copper versus
cast iron. Think of the fl y fi sher who can sense the presence of
trout and accurately judge the likely species, make the right
choice of dry fl y, nymph, or streamer, judge the wind, and
know how and where to drop that fl y to make the trout rise.
Think of the kid on the BMX bike who can perform bunnyhops,
tail whips, 180s, and wall taps off the features of an
unfamiliar streetscape. Interleaving and variation mix up the
contexts of practice and the other skills and knowledge with
which the new material is associated. This makes our mental
models more versatile, enabling us to apply our learning to a
broader range of situations.
Fostering Conceptual Learning
How do humans learn concepts, for example the difference
between dogs and cats? By randomly coming across dissimilar
examples— Chihuahuas, tabby cats, Great Danes, picture
book lions, calico cats, Welsh terriers. Spaced and interleaved
exposure characterizes most of humans’ normal experience.
It’s a good way to learn, because this type of exposure strengthens
the skills of discrimination— the pro cess of noticing particulars
(a turtle comes up for air but a fi sh doesn’t)— and of
induction: surmising the general rule (fi sh can breathe in water).
Recall the interleaved study of birds in one case, and of
paintings in another, that helped learners distinguish between
bird types or the works of different paint ers while at the same
time learning to identify underlying commonalities of the
examples within a species or an artist’s body of work. When
asked about their preferences and beliefs, the learners thought
Embrace Difficulties ê 85
that the experience of studying multiple examples of one species
of bird before studying examples of another species resulted
in better learning. But the interleaved strategy, which
was more diffi cult and felt clunky, produced superior discrimination
of differences between types, without hindering the
ability to learn commonalities within a type. As was true for
the baseball players’ batting practice, interleaving produced
diffi culty in retrieving past examples of a par tic u lar species,
which further solidifi ed the learning of which birds are representative
of a par tic u lar species.
The diffi culty produced by interleaving provides a second
type of boost to learning. Interleaved practice of related but
dissimilar geometric solids requires that you notice similarities
and differences in order to select the correct formula for
computing the volume. It’s thought that this heightened sensitivity
to similarities and differences during interleaved practice
leads to the encoding of more complex and nuanced
repre sen ta tions of the study material— a better understanding
of how specimens or types of problems are distinctive and
why they call for a different interpretation or solution. Why a
northern pike will strike a spoon or a crankbait, say, but a
bass will happily powder his nose until you see fi t to throw
him a grub or a popper.12
Improving Versatility
The retrieval diffi culties posed by spacing, interleaving, and
variation are overcome by invoking the same mental processes
that will be needed later in applying the learning in everyday
settings. By mimicking the challenges of practical experience,
these learning strategies conform to the admonition
to “practice like you play, and you’ll play like you practice,”
improving what scientists call transfer of learning, which is
Make It Stick ê 86
the ability to apply what you’ve learned in new settings. In the
Cal Poly batting practice experiment, the act of overcoming
the diffi culties posed by random types of pitches built a
broader “vocabulary” of mental pro cesses for discerning the
nature of the challenge (e.g., what the pitcher is throwing)
and selecting among possible responses than did the narrower
mental pro cesses suffi cient for excelling during massed, nonvaried
experience. Recall the grade school students who proved
more adept at tossing beanbags into three- foot baskets after
having practiced tossing into two- and four- foot baskets, compared
to the students who only practiced tossing into threefoot
basket. Recall the increasing diffi culty and complexity of
the simulation training in jump school, or the cockpit simulator
of Matt Brown’s business jet.
Priming the Mind for Learning
When you’re asked to struggle with solving a problem before
being shown how to solve it, the subsequent solution is better
learned and more durably remembered. When you’ve bought
your fi shing boat and are attempting to attach an anchor line,
you’re far more likely to learn and remember the bowline knot
than when you’re standing in a city park being shown the bowline
by a Boy Scout who thinks you would lead a richer life if
you had a handful of knots in your repertoire.
Other Learning Strategies That Incorporate
Desirable Diffi culties
We usually think of interference as a detriment to learning,
but certain kinds of interference can produce learning benefi
ts, and the positive effects are sometimes surprising. Would
you rather read an article that has normal type or type that’s
somewhat out of focus? Almost surely you would opt for the
Embrace Difficulties ê 87
former. Yet when text on a page is slightly out of focus or
presented in a font that is a little diffi cult to decipher, people
recall the content better. Should the outline of a lecture follow
the precise fl ow of a chapter in a textbook, or is it better if the
lecture mismatches the text in some ways? It turns out that
when the outline of a lecture proceeds in a different order from
the textbook passage, the effort to discern the main ideas and
reconcile the discrepancy produces better recall of the content.
In another surprise, when letters are omitted from words
in a text, requiring the reader to supply them, reading is slowed,
and retention improves. In all of these examples, the change
from normal pre sen ta tion introduces a diffi culty— disruption
of fl uency— that makes the learner work harder to construct
an interpretation that makes sense. The added effort increases
comprehension and learning. (Of course, learning will not
improve if the diffi culty completely obscures the meaning or
cannot be overcome.)13
The act of trying to answer a question or attempting to solve
a problem rather than being presented with the information
or the solution is known as generation. Even if you’re being
quizzed on material you’re familiar with, the simple act of fi lling
in a blank has the effect of strengthening your memory of
the material and your ability to recall it later. In testing, being
required to supply an answer rather than select from multiple
choice options often provides stronger learning benefi ts. Having
to write a short essay makes them stronger still. Overcoming
these mild diffi culties is a form of active learning, where
students engage in higher- order thinking tasks rather than
passively receiving knowledge conferred by others.
When you’re asked to supply an answer or a solution to
something that’s new to you, the power of generation to aid
Make It Stick ê 88
learning is even more evident. One explanation for this effect
is the idea that as you cast about for a solution, retrieving related
knowledge from memory, you strengthen the route to a
gap in your learning even before the answer is provided to fi ll
it and, when you do fi ll it, connections are made to the related
material that is fresh in your mind from the effort. For example,
if you’re from Vermont and are asked to name the
capital of Texas you might start ruminating on possibilities:
Dallas? San Antonio? El Paso? Houston? Even if you’re unsure,
thinking about alternatives before you hit on (or are
given) the correct answer will help you. (Austin, of course.)
Wrestling with the question, you rack your brain for something
that might give you an idea. You may get curious, even
stumped or frustrated and acutely aware of the hole in your
knowledge that needs fi lling. When you’re then shown the solution,
a light goes on. Unsuccessful attempts to solve a problem
encourage deep pro cessing of the answer when it is later
supplied, creating fertile ground for its encoding, in a way
that simply reading the answer cannot. It’s better to solve a
problem than to memorize a solution. It’s better to attempt a
solution and supply the incorrect answer than not to make
the attempt.14
The act of taking a few minutes to review what has been
learned from an experience (or in a recent class) and asking
yourself questions is known as refl ection. After a lecture or
reading assignment, for example, you might ask yourself:
What are the key ideas? What are some examples? How do
these relate to what I already know? Following an experience
where you are practicing new knowledge or skills, you might
ask: What went well? What could have gone better? What
Embrace Difficulties ê 89
might I need to learn for better mastery, or what strategies
might I use the next time to get better results?
Refl ection can involve several cognitive activities we have
discussed that lead to stronger learning. These include retrieval
(recalling recently learned knowledge to mind), elaboration
(for example, connecting new knowledge to what you
already know), and generation (for example, rephrasing key
ideas in your own words or visualizing and mentally rehearsing
what you might do differently next time).
One form of refl ection that is gaining currency in classroom
settings is called “write to learn.” In essence, students
refl ect on a recent class topic in a brief writing assignment,
where they may express the main ideas in their own words
and relate them to other concepts covered in class, or perhaps
outside class. (For an example, read in Chapter 8 about the
“learning paragraphs” Mary Pat Wenderoth assigns her students
in her human physiology course.) The learning benefi ts
from the various cognitive activities that are engaged during
refl ection (retrieval, elaboration, generation) have been well
established through empirical studies.
An interesting recent study specifi cally examined “write to
learn” as a learning tool. Over eight hundred college students
in several introductory psychology classes listened to lectures
throughout the semester. Following the pre sen ta tion of a key
concept within a given lecture, the instructor asked students
to write to learn. Students generated their own written summaries
of the key ideas, for example restating concepts in their
own words and elaborating on the concepts by generating
examples of them. For other key concepts presented during
the lecture, students were shown a set of slides summarizing
the concepts and spent a few minutes copying down key ideas
and examples verbatim from the slide.
Make It Stick ê 90
What was the result? On exams administered during the
semester, the students were asked questions that assessed their
understanding of the key concepts that they had worked on
learning. They scored signifi cantly (approximately half a letter
grade) better on the ones they had written about in their
own words than on those they had copied, showing that it
was not simply exposure to the concepts that produced the
learning benefi t. In follow- up tests approximately two months
later to mea sure retention, the benefi ts of writing to learn as a
form of refl ection had dropped but remained robust.15
Failure and the Myth of Errorless Learning
In the 1950s and 1960s, the psychologist B. F. Skinner advocated
the adoption of “errorless learning” methods in education
in the belief that errors by learners are counterproductive
and result from faulty instruction. The theory of errorless
learning gave rise to instructional techniques in which learners
were spoonfed new material in small bites and immediately
quizzed on them while they still remained on the tongue,
so to speak, fresh in short- term memory and easily spit out
onto the test form. There was virtually no chance of making
an error. Since those days we’ve come to understand that retrieval
from short- term memory is an in effec tive learning
strategy and that errors are an integral part of striving to increase
one’s mastery over new material. Yet in our Western
culture, where achievement is seen as an indicator of ability,
many learners view errors as failure and do what they can to
avoid committing them. The aversion to failure may be reinforced
by instructors who labor under the belief that when
learners are allowed to make errors it’s the errors that they
will learn.16
This is a misguided impulse. When learners commit errors
and are given corrective feedback, the errors are not learned.
Embrace Difficulties ê 91
Even strategies that are highly likely to result in errors, like
asking someone to try to solve a problem before being shown
how to do it, produce stronger learning and retention of the
correct information than more passive learning strategies, provided
there is corrective feedback. Moreover, people who are
taught that learning is a struggle that often involves making
errors will go on to exhibit a greater propensity to tackle
tough challenges and will tend to see mistakes not as failures
but as lessons and turning points along the path to mastery.
To see the truth of this, look no further than the kid down the
hall who is deeply absorbed in working his avatar up through
the levels of an action game on his Xbox video console.
A fear of failure can poison learning by creating aversions
to the kinds of experimentation and risk taking that characterize
striving, or by diminishing per for mance under pressure,
as in a test setting. In the latter instance, students who have a
high fear of making errors when taking tests may actually do
worse on the test because of their anxiety. Why? It seems that
a signifi cant portion of their working memory capacity is expended
to monitor their per for mance (How am I doing? Am I
making mistakes?), leaving less working memory capacity
available to solve the problems posed by the test. “Working
memory” refers to the amount of information you can hold in
mind while working through a problem, especially in the face
of distraction. Everyone’s working memory is severely limited,
some more than others, and larger working memory capacities
correlate with higher IQs.
To explore this theory about how fear of failure reduces
test per for mance, sixth graders in France were given very diffi
cult anagram problems that none of them could solve. After
struggling unsuccessfully with the problems, half of the kids
received a ten- minute lesson in which they were taught that
diffi culty is a crucial part of learning, errors are natural and
to be expected, and practice helps, just as in learning to ride a
Make It Stick ê 92
bicycle. The other kids were simply asked how they had gone
about trying to solve the anagrams. Then both groups were
given a diffi cult test whose results provided a mea sure of
working memory. The kids who had been taught that errors
are a natural part of learning showed signifi cantly better use
of working memory than did the others. These children did not
expend their working memory capacity in agonizing over the
diffi culty of the task. The theory was further tested in variations
of the original study. The results support the fi nding that
diffi culty can create feelings of incompetence that engender
anxiety, which in turn disrupts learning, and that “students do
better when given room to struggle with diffi culty.”17
These studies point out that not all diffi culties in learning
are desirable ones. Anxiety while taking a test seems to represent
an undesirable diffi culty. These studies also underscore
the importance of learners understanding that diffi culty in
learning new things is not only to be expected but can be benefi
cial. To this point, the French study stands on the shoulders
of many others, among the foremost being the works of Carol
Dweck and of Anders Ericsson, both of whom we discuss in
Chapter 7 in relation to the topic of increasing intellectual
abilities. Dweck’s work shows that people who believe that
their intellectual ability is fi xed from birth, wired in their
genes, tend to avoid challenges at which they may not succeed,
because failure would appear to be an indication of lesser native
ability. By contrast, people who are helped to understand
that effort and learning change the brain, and that their intellectual
abilities lie to a large degree within their own control,
are more likely to tackle diffi cult challenges and persist at
them. They view failure as a sign of effort and as a turn in the
road rather than as a mea sure of inability and the end of the
road. Anders Ericsson’s work investigating the nature of expert
per for mance shows that to achieve expertise requires thouEmbrace
Difficulties ê 93
sands of hours of dedicated practice in which one strives to
surpass one’s current level of ability, a pro cess in which failure
becomes an essential experience on the path to mastery.
The study of the French sixth graders received wide publicity
and inspired the staging of a “Festival of Errors” by an elite
graduate school in Paris, aimed at teaching French schoolchildren
that making mistakes is a constructive part of learning:
not a sign of failure but of effort. Festival organizers argued
that modern society’s focus on showing results has led to a
culture of intellectual timorousness, starving the kind of intellectual
ferment and risk-taking that produced the great discoveries
that mark French history.
It doesn’t require a great conceptual leap to get from Paris’s
“Festival of Errors” to San Francisco’s “FailCon,” where
technology entrepreneurs and venture capitalists meet once a
year to study failures that gave them critical insights they
needed in order to pivot in their business strategies so as to
succeed. Thomas Edison called failure the source of inspiration,
and is said to have remarked, “I’ve not failed. I’ve just
found 10,000 ways that don’t work.” He argued that perseverance
in the face of failure is the key to success.
Failure underlies the scientifi c method, which has advanced
our understanding of the world we inhabit. The qualities of
per sis tence and resiliency, where failure is seen as useful information,
underlie successful innovation in every sphere and lie
at the core of nearly all successful learning. Failure points to
the need for redoubled effort, or liberates us to try different
approaches. Steve Jobs, in his remarks to the Stanford University
graduating class of 2005, spoke of being fi red at age thirty
in 1985 from Apple Computer, which he had cofounded. “I
didn’t see it then, but it turned out that getting fi red from Apple
was the best thing that could have ever happened to me.
The heaviness of being successful was replaced by the lightness
Make It Stick ê 94
of being a beginner again, less sure about everything. It freed
me to enter one of the most creative periods of my life.”
It’s not the failure that’s desirable, it’s the dauntless effort
despite the risks, the discovery of what works and what doesn’t
that sometimes only failure can reveal. It’s trusting that trying
to solve a puzzle serves us better than being spoon- fed the solution,
even if we fall short in our fi rst attempts at an answer.
An Example of Generative Learning
As we said earlier, the pro cess of trying to solve a problem
without the benefi t of having been taught how is called generative
learning, meaning that the learner is generating the
answer rather than recalling it. Generation is another name
for old- fashioned trial and error. We’re all familiar with the
stories of skinny kids in Silicon Valley garages messing around
with computers and coming out billionaires. We would like to
serve up a different kind of example here: Minnesota’s Bonnie
Blodgett.
Bonnie is a writer and a self- taught ornamental gardener in
a constant argument with a voice in her head that keeps nattering
about all the ways her latest whim is sure to go haywire
and embarrass her. While she is a woman of strong aesthetic
sensibilities, she is also one of epic doubts. Her “learning
style” might be called leap- before- you- look- because- if- youlook-
fi rst- you- probably- won’t-like- what- you- see. Her garden
writing appears under the name “The Blundering Gardener.”
This moniker is a way of telling her voices of doubt to take a
hike, because what ever the consequences of the next whim,
she’s already rolling up her sleeves. “Blundering means that
you get going on your project before you have fi gured out
how to do it in the proper way, before you know what you’re
getting into. For me, the risk of knowing what you’re getting
Embrace Difficulties ê 95
into is that it becomes an overwhelming obstacle to getting
started.”18
Bonnie’s success shows how struggling with a problem
makes for strong learning, and how a sustained commitment
to advancing in a par tic u lar fi eld of endeavor through trialand-
error effort leads to complex mastery and greater knowledge
of the interrelationships of things. When we spoke, she
had just traveled to southern Minnesota to meet with a group
of farmers who wanted her gardening insights on a gamut of
issues ranging from layout and design to pest control and irrigation.
In the years since she fi rst sank her spade, Bonnie’s
garden writing has won national recognition and found a devoted
following far and wide through many outlets, and her
garden has become a destination for other gardeners.
She came to ornamental gardening about the time she
found herself eyeballing middle age. She had no training, just
a burning desire to get her hands dirty making beautiful spaces
on the corner lot of the home she shares with her husband in
a historic neighborhood of St. Paul.
“The experience of creating beauty calms me down,” she
says, but it’s strictly a discovery pro cess. She has always been
a writer, and some years after having launched herself into the
garden, she began publishing the Garden Letter, a quarterly
for northern gardeners in which she chronicles her exploits,
mishaps, lessons, and successes. She writes the same way that
she gardens, with boldness and self- effacing humor, passing
along the entertaining snafus and unexpected insights that are
the fruits of experience. In calling herself the Blundering Gardener,
she is giving herself and us, her readers, permission to
make mistakes and get on with it.
Note that in writing about her experiences, Bonnie is engaging
two potent learning pro cesses beyond the act of gardening
itself. She is retrieving the details and the story of what
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she has discovered— say, about an experiment in grafting two
species of fruit trees— and then she is elaborating by explaining
the experience to her readers, connecting the outcome to
what she already knows about the subject or has learned as a
result.
Her leap- taking impulses have taken her through vast
swaths of the plant kingdom, of course, and deeply into the
Latin nomenclature and the classic horticultural literature.
These impulses have also drawn her into the aesthetics of
space and structure and the mechanics thereof: building stone
walls; digging and wiring water features; putting a cupola on
the garage; building paths, stairs, and gates; ripping out a
Gothic picket fence and reusing the wood to create something
more open and with stronger horizontal lines to pull down
the soaring verticality of her three- story Victorian house and
connect it with the gardens that surround it; making the outdoor
spaces airier and more easily seen from the street, while
still circumscribed, so as to impart that essential sense of privacy
that makes a garden a room of its own. Her spaces are
idiosyncratic and asymmetrical, giving the illusion of having
evolved naturally, yet they cohere, through the repetition of
textures, lines, and geometry.
A simple example of how she has backed into more and
more complex mastery is the manner in which she came to
embrace plant classifi cation and the Latin terminology. “When
I started, the world of plants was a completely foreign language
to me. I would read gardening books and be completely
lost. I didn’t know what plant names were, common or Latin.
I wasn’t thinking about learning this stuff, ever. I’m like, Why
would you want to do that? Why wouldn’t you just get outside
and dig a hole and put something in it?” What she relished
were pictures that gave her ideas and passages of text
where the designers used phrases like “my pro cess” in describing
Embrace Difficulties ê 97
how they had achieved the desired effect. It was the possessive
pronoun, my pro cess, that affi rmed Bonnie in her headlong
rush to learn by doing. The notion is that every gardener’s
pro cess is uniquely his or her own. Bonnie’s pro cess did not
involve taking direction from experts, much less mastering
the Linnaean taxonomy or the Latin names of what she stuck
in holes and dragged her water hose to. But as she thrashed
around, working to achieve in dirt the magical spaces that
danced in her mind, she came to Latin and Linnaeus despite
herself.
“You begin to discover that the Latin names are helpful.
They can give you a shortcut to understanding the nature of
the plants, and they can help you remember. Tardiva, which
is a species name, comes after hydrangea, which is a genus.”
Bonnie had taken Latin in high school, along with French,
and of course En glish, and the cues to those memories began
to reawaken. “I can easily see that tardiva means late, like
tardy. The same word comes after many plant varieties, so
you see the genus and then the species is tardiva, and now
you know that par tic u lar plant is a late bloomer. So you begin
to realize that the Latin names are a way of helping you
remember, and you fi nd yourself using them more and more.
Also you remember plants better, because it’s second nature
to you that procumbus means prostrate, crawling on the
ground. It makes sense. So now it’s not so hard to remember
that par tic u lar species name when it’s attached to a genus.
It’s also important to know the Latin names because then
you can be absolutely specifi c about a plant. Plants have
common names, and common names are regional. Actaea
racemosa has a common name of black cohosh, but it’s also
known as snakeroot, and those names are often given to
other plants. There’s only one Actaea racemosa.” Gradually,
and despite her inclination to resist, she came to grasp the
Make It Stick ê 98
classical taxonomy of ornamental plants and to appreciate
how Linnaeus’s schema frames family connections and communicates
attributes.
Bonnie said that the farmers she had recently met were
particularly interested in what she has learned about the advantages
of composting and earthworms over chemical fertilizers
for building nutrients and soil aeration, and how to get
strong root growth on low rations of water through a homemade
system of drip irrigation. She paused in recounting her
meeting with them, refl ecting on how all of this knowledge
has sneaked up on her. It was never something she set out to
conquer. “Look, blundering’s really not a bad thing. It’s a good
thing in that you get stuff done. A lot of people, when they
contemplate the enormity of the task and they see all that’s
entailed, they’re stopped in their tracks.”
Of course, in some settings— like learning to jump out of
airplanes and walk away with your life— blundering is not
the optimal learning strategy.
Undesirable Diffi culties
Elizabeth and Robert Bjork, who coined the phrase “desirable
diffi culties,” write that diffi culties are desirable because “they
trigger encoding and retrieval pro cesses that support learning,
comprehension, and remembering. If, however, the learner
does not have the background knowledge or skills to respond
to them successfully, they become undesirable diffi culties.”19
Cognitive scientists know from empirical studies that testing,
spacing, interleaving, variation, generation, and certain kinds
of contextual interference lead to stronger learning and retention.
Beyond that, we have an intuitive sense of what kinds of
diffi culties are undesirable but, for lack of the needed research,
we cannot yet be defi nitive.
Embrace Difficulties ê 99
Clearly, impediments that you cannot overcome are not
desirable. Outlining a lesson in a sequence different from the
one in the textbook is not a desirable diffi culty for learners
who lack the reading skills or language fl uency required to
hold a train of thought long enough to reconcile the discrepancy.
If your textbook is written in Lithuanian and you don’t
know the language, this hardly represents a desirable diffi -
culty. To be desirable, a diffi culty must be something learners
can overcome through increased effort.
Intuitively it makes sense that diffi culties that don’t
strengthen the skills you will need, or the kinds of challenges
you are likely to encounter in the real- world application of
your learning, are not desirable. Having somebody whisper
in your ear while you read the news may be essential training
for a TV anchor. Being heckled by role- playing protestors
while honing your campaign speech may help train up a politician.
But neither of these diffi culties is likely to be helpful for
Rotary Club presidents or aspiring YouTube bloggers who
want to improve their stage presence. A cub towboat pi lot on
the Mississippi might be required in training to push a string
of high- riding empty barges into a lock against a strong side
wind. A baseball player might practice hitting with a weight
on his bat to strengthen his swing. You might teach a football
player some of the principles of ballet for learning balance and
movement, but you probably would not teach him the techniques
for an effective golf drive or backhand tennis serve.
Is there an overarching rule that determines the kinds of
impediments that make learning stronger? Time and further
research may yield an answer. But the kinds of diffi culties
we’ve just described, whose desirability is well documented,
offer a large and diverse toolkit already at hand.
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The Takeaway
Learning is at least a three- step pro cess: initial encoding of
information is held in short- term working memory before being
consolidated into a cohesive repre sen ta tion of knowledge
in long- term memory. Consolidation reorganizes and stabilizes
memory traces, gives them meaning, and makes connections
to past experiences and to other knowledge already
stored in long- term memory. Retrieval updates learning and
enables you to apply it when you need it.
Learning always builds on a store of prior knowledge. We
interpret and remember events by building connections to
what we already know.
Long- term memory capacity is virtually limitless: the more
you know, the more possible connections you have for adding
new knowledge.
Because of the vast capacity of long- term memory, having
the ability to locate and recall what you know when you need
it is key; your facility for calling up what you know depends
on the repeated use of the information (to keep retrieval routes
strong) and on your establishing powerful retrieval cues that
can reactivate the memories.
Periodic retrieval of learning helps strengthen connections
to the memory and the cues for recalling it, while also weakening
routes to competing memories. Retrieval practice that’s
easy does little to strengthen learning; the more diffi cult the
practice, the greater the benefi t.
When you recall learning from short- term memory, as in
rapid- fi re practice, little mental effort is required, and little
long- term benefi t accrues. But when you recall it after some
time has elapsed and your grasp of it has become a little rusty,
you have to make an effort to reconstruct it. This effortful
retrieval both strengthens the memory but also makes the
Embrace Difficulties ê 101
learning pliable again, leading to its reconsolidation. Reconsolidation
helps update your memories with new information
and connect them to more recent learning.
Repeated effortful recall or practice helps integrate learning
into mental models, in which a set of interrelated ideas or
a sequence of motor skills are fused into a meaningful whole
that can be adapted and applied in later settings. Examples
are the perceptions and manipulations involved in driving a
car or in knocking a curveball out of the ballpark.
When practice conditions are varied or retrieval is interleaved
with the practice of other material, we increase our
abilities of discrimination and induction and the versatility
with which we can apply the learning in new settings at a
later date. Interleaving and variation build new connections,
expanding and more fi rmly entrenching knowledge in memory
and increasing the number of cues for retrieval.
Trying to come up with an answer rather than having it
presented to you, or trying to solve a problem before being
shown the solution, leads to better learning and longer retention
of the correct answer or solution, even when your attempted
response is wrong, so long as corrective feedback is
provided.