When Can You Trust the Experts?

How to Tell Good Science from Bad in Education

Daniel T. Willingham

• Publisher: Jossey-Bass
• Year: 2012
• ISBN:
  9781118233276
• Edition: 1
• Topic: Didattica
• Subtopic: Didattica della scienza e della tecnologia

Clear, easy principles to spot what's nonsense and what's reliable

Each year, teachers, administrators, and parents face a barrage of new education software, games, workbooks, and professional development programs purporting to be "based on the latest research." While some of these products are rooted in solid science, the research behind many others is grossly exaggerated. This new book, written by a top thought leader, helps everyday teachers, administrators, and family members—who don't have years of statistics courses under their belts—separate the wheat from the chaff and determine which new educational approaches are scientifically supported and worth adopting.

• Author's first book, Why Don't Students Like School?, catapulted him to superstar status in the field of education
• Willingham's work has been hailed as "brilliant analysis" by The Wall Street Journal and "a triumph" by The Washington Post
• Author blogs for The Washington Post and Brittanica.com, and writes a column for American Educator

In this insightful book, thought leader and bestselling author Dan Willingham offers an easy, reliable way to discern which programs are scientifically supported and which are the equivalent of "educational snake oil."

Part One

Why We So Easily Believe Bad Science

Chapter 1

Why Smart People Believe Dumb Things

It is useless to attempt to reason a man out of a thing he was never reasoned into.

—Jonathan Swift

Suppose you’re in a library, and you need to photocopy some pages from a book. You find the copy machine, and happily you discover that you have some quarters. You’re about to drop a coin in the slot when a stranger approaches you. He asks whether he can use the photocopier. Would you let the stranger use the machine, or would you politely decline, given that, after all, you were there first?

In this chapter, we will be less interested in whether or not you would comply with this request, and more interested in whether or not you would think before answering. It would seem that a social interaction—deciding whether or not to grant a small favor—would require thought. But it doesn’t, according to a landmark study conducted by Ellen Langer.1 An experimenter approached individuals just as they were about to use a coin-operated copy machine, with one of three requests:

1. Excuse me, I have five pages. May I use the Xerox machine?

2. Excuse me, I have five pages. May I use the Xerox machine, because I’m in a rush?

3. Excuse me, I have five pages. May I use the Xerox machine, because I have to make copies?

The first request offers no reason, whereas the second offers a socially acceptable reason. The third request is odd. It offers a reason that is not a reason—if you’re asking to use the photocopier, then obviously you have to make copies.

The surprising finding was that people found this nonreason persuasive. Sixty percent of people complied with the request when no reason was offered, but 93 percent complied when the nonsensical “reason” was added—about the same percentage as when the bona fide reason was added. What’s going on?

Langer argued that people are not thinking during this seemingly complex interchange. People are willing to do small favors for strangers, especially if the stranger makes the request politely and if the stranger offers some reason for the imposition. What the experiment seems to show is that the person hears the word “because” in the request and thus knows that a reason has been offered, but the person doesn’t take the trouble to evaluate the quality of the reason.

The idea that we are on autopilot even when we engage in complex behaviors is familiar to most of us. Obviously, you don’t need to consciously guide the movements of your hands as you button your shirt in the morning or tie your shoes; you did consciously control those movements at age two or three, but now they have become automatic. And routinized behaviors can be more complex than simple movements like shoe tying. You’ve probably found yourself pulling your car into your driveway and realizing that you had daydreamed the whole way home—stewed about a problem or fantasized about a vacation—and all the while obeyed traffic laws, braked for pedestrians, made the correct turns, and so on. It’s as though there is a computer program in your mind that you initiate when you climb in the car, and the “drive home” program runs without your supervision, leaving you free to think about other things.

An autopilot program is especially noticeable if it plays at a moment you wish it wouldn’t. If you want to stop at the supermarket on the way home, you may well find yourself in your driveway without having made the stop. The “drive home” program dictates a left turn at Elm Street, and you didn’t interrupt it to make sure that you took a right to go to the market. Or, to use the example offered by the great nineteenth-century psychologist William James, “Very absent-minded persons in going to their bedrooms to dress for dinner have been known to take off one garment after another and finally to get into bed, merely because that was the habitual issue of the first few movements when performed at a later hour.”2

This phenomenon—that consciousness may contribute little or nothing to the initiation of complex behaviors and the making of complex decisions—has created something of a revolution in social psychology. Researchers have discovered that more and more of the thought that drives our social lives happens outside of awareness.a

Here’s another example. When you speak with someone who has an accent, have you ever noticed yourself slipping into the accent yourself, without quite noticing that you’re doing so?b This is an instance of a more general phenomenon: humans imitate each other during social interactions.3 In one experiment demonstrating this phenomenon, subjects were paired with someone they thought was another subject, but who was actually a research assistant. The pair was to describe the contents of ambiguous photographs. During the task, the research assistant engaged in one of two nervous habits—either shaking her foot or touching her face. The subjects unconsciously mimicked the behavior of the research assistant.

Why do we mimic? Mimicry breeds liking. We like people who are similar to us. In First Corinthians, Paul says, “To the Jews I became like a Jew, to win the Jews. To those under the law, I became like one under the law to win those under the law. To the weak, I became weak, to win the weak.”4 Similarity aids persuasion even when based on something as trivial as having the same nervous tic or taking an ice cream sample of similar size.5 We unconsciously imitate each other to smooth social interactions.

The emerging picture is that we have two modes of social interaction. One is conscious and involves the logical integration of evidence. For example, a waiter puts the check down on the table and says to me, “I hope you enjoyed your meal!” I think to myself that the steak was a bit tough, but the salad was expertly prepared. Consciously weighing the good and the bad, I offer the waiter a measured comment like “Yeah, it was pretty good.” In the other, automatic mode, I merely detect certain cues or signals that mark the waiter’s comment to me as belonging to a category of social interactions—in this case, “social pleasantry.” Other categories might be “acquaintance asks a small favor” or “perform a task with a stranger.” Once I’ve identified the category, I can act appropriately to the situation (grant the favor, mimic the stranger) with little or no conscious thought. Sometimes this mental process goes wrong. We miscategorize what someone has said, or the automatically generated behavior doesn’t quite fit. More than once, a waiter has set a check on my table and said with a farewell intonation, “Enjoy the rest of your dessert!” and I’ve responded “Thanks, you too.” My unconscious mind coded the waiter’s comment as a social pleasantry and then my unconscious mind generated a response that typically works, but in this case was inappropriate.

Unconscious Persuasion

If indeed we have two modes of social thought—conscious and unconscious—is each mode capable of evaluating persuasive messages? Can persuasion happen outside awareness or, at least, with little thought? The answer is an emphatic yes.6

First, let’s be clear what unconscious persuasion does not mean. You may have heard about subliminal (that is, unconscious) persuasion effects in advertisements. The idea is that advertisers embed messages in their ads that are not consciously perceived but will nonetheless affect behavior. For example, the words EAT POPCORN might appear in a single frame of a movie, too briefly for the conscious mind to perceive. Or a stylized sexual image might be worked into a product photograph—for example, a swirl of butter that, if you squint, looks a bit like a woman’s breast. The theory is that the hidden message or drawing will still be perceived unconsciously, leaving the moviegoer with a yen for popcorn and the magazine reader thinking that a particular brand of butter is somehow strangely appealing.

This idea has been around since the 1950s7 and seems to be perennial,8 probably because it’s such a fascinating, if chilling, possibility. Researchers have found it interesting as well, and lots of evidence compiled in the last few decades shows that this sort of subliminal persuasion doesn’t work.c There are some circumstances in which stimuli you don’t consciously see can influence your behavior, but the behaviors subject to this influence are pretty low-level laboratory tasks that wouldn’t have much impact in your daily life, such as how rapidly you can verify that a string of letters forms a word (“bread”) rather than a nonword (“plonch”). You can’t get people to buy popcorn or other products with this method.

The real concern is not that you are persuaded by things outside your awareness. The real concern arises when you’re aware of these messages but don’t recognize that they persuade you. Subjects who surrendered the copier were aware of the request, but surely did not notice that their response was prompted by the phantom “reason” given by the experimenter. The cue “reason offered” tells our inattentive mind to accede to an innocuous request from a stranger. What are the cues that tell our inattentive mind “This message is probably true”?

Familiar Ideas Are More Believable

One such cue is familiarity. Things that are familiar seem reliable, safe, likable, and believable.9 In a typical experiment investigating this phenomenon, subjects heard a series of statements presented as little-known facts—for example, that comedian Bob Hope’s father was a fireman or that the right arm of the Statue of Liberty is forty-two feet long.10 (The “facts” were fabricated, to be certain that subjects could not have known any of them before the experiment.) Later, subjects were presented with a set of trivia statements of the same sort, and they were asked to judge the likelihood that each is true. Some of the statements were repetitions of the prior set, and these statements were judged as more likely to be true. The effect is just as large if you tell subjects which statements were presented earlier and warn them that “these statements might feel true just because you heard them recently.”11

Even more remarkable, familiarity affects credibility even if people know they shouldn’t believe the source at the time. In one experiment, subjects were told who made each statement—for example, “John Yates says that three hundred thousand pencils can be made from the average cedar tree.”12 Subjects were told that statements from males were always accurate and that statements from females were always inaccurate. (Half of the subjects were told the opposite gender-truth relationship.) Later, subjects read a list of statements, with the instruction to judge the credibility of each. They were told that they had heard some of the statements earlier in the experiment, and they were reminded that some of them were false. So what happened?

Familiar statements were still judged as more likely to be true. Why? Well, during the trivia test when a subject reads, “Eighteen newborn possums can be placed in a teaspoon,” she might say to herself, “Hmm . . . that seems familiar. Did I hear that during the experiment, or is it just one of those odd facts you pick up somewhere?” If she doesn’t remember hearing it during the experiment, she will judge that it’s true. But even if she remembers hearing it during the experiment, she still might not remem...