It rarely occurs to less-educated persons that what gets learned during scientific training is not an exotic body of facts, but rather a set of logical and critical thinking skills. This is why scientists, in the main, are skeptics, whereas less-educated people are not. Authority, as a reason for belief, holds almost no allure to most scientists, whereas it is distressingly persuasive to people with less education. Higher education, especially in the sciences, leaves one with mantras such as “To live is to question” or “Doubt is everything.” As comedian Bill Maher says, “Keep asking questions or it becomes a religion.” These viewpoints do not translate well across cultural lines. Indeed, questioning or doubting may well be seen as a sign of disrespect in less-educated subcultures. Certainly, we know that most organized religions do not nurture such tendencies among their members.
Scientific education makes several specific contributions to a healthy intellectual life. First, like most higher education, it leaves us with a high regard for just how much we do
not
know. The more education one has, the more he or she is likely to profess ignorance. It is that simple.
Second, even those things that are known have a somewhat tentative quality. Most scientific knowledge comes with an expiry date on the label. Things appear correct within the present context. But as our knowledge grows, we often have to question and reevaluate our present collection of “facts.” Some students find the tentative nature of knowledge to be infuriating, even intolerable. Such persons have an easy time of it; there are many alternative belief systems out there that offer absolute facts. Just accept and there is no need to question or doubt. A black and white universe is there for the taking, and you’ll have the company of like-minded persons in the bargain. About the only thing you sacrifice is accuracy. But when was accuracy ever a competitor to comfort and reassurance?
So far the legacy of a scientific education seems to be a knowledge that we actually know very little. Added to that, it is
difficult
to know things and what we
do
know is subject to change as our knowledge grows. You can see why science education is not a product with particularly wide appeal, given the competition. This is probably the time to admit that not all scientific training is created equal. Gilovich has made an important distinction between what he terms the “deterministic” versus the “probabilistic” sciences. When I went to graduate school in psychology, several friends used to tease me that I ought to get into a “real” science. Even my first-year professors admitted that psychologists were often self-conscious about their lack of scientific precision. We were given a sense that, as sciences went, psychology was a second-class citizen. “Real” sciences, like chemistry and physics and astronomy, typically made statements about relationships in the physical universe. Gravity wasn’t something that worked nineteen out of twenty times. You stick potassium permanganate and glycerine together in a test tube and there wasn’t a .95 chance the compounds would react violently. They simply did. Truth is truth. Determinism, we were told, was the basis of real science.
In turn, we in psychology were offered a probabilistic view of the universe. This is the way things are most of the time, we were told. But the truth is, we’re dealing with a very complex, multivariate universe and since we don’t really have a handle on all those other factors, the best we can do is state with some statistical probability that we understand the relationship we’re studying. You want precision, we were told somewhat defensively, go study geology or chemistry. In time, we all got used to it. About the only downside was that we had to learn all about inferential statistics and fancy multivariate procedures in order to wrestle meaning out of the jumble of results our experiments produced. But the truth is, the universe is a messy place. It’s not so much that God is playing dice with it, as Einstein famously observed, but that even the simplest situation was awash in factors that could be functionally related to what you were studying. You control as many of them as you can and hope for the best. Even a lone rat in an impoverished-looking Skinner box can be an explanatory nightmare. You give it your best shot and if your results can be replicated nineteen out of twenty times, you get to hold your head up with the big boys. It may be far from physics or chemistry, but it’s how most of us do business in psychology.
Now, all these years later, it turns out there may actually have been an advantage to being a psychologist. Gilovich argues that traditional hard sciences such as physics and chemistry deal largely with a straightforward determinist universe and, as such, offer little in the way of useful scientific method when one is confronted by unusual or speculative belief systems. In contrast, psychology offers a more appropriate logical framework from which to evaluate such claims. Things are not so black and white within the psychological universe. Patience, skepticism, and even-handedness are useful skills to have when faced with what Gilovich calls the “messy probabilistic phenomena that are often encountered in everyday life.” Causes are usually multiple; even when we find one, it may be necessary, but it is rarely sufficient to account for the event in question. Psychologists are often challenged by tough cases. Behavior and perception may reveal as much about the mind of the individual as they do about the world outside.
Evolutionary psychology and cognitive neuroscience have helped us to see that we are not simply blank slates, responding to the external environment. The evolved structure of our minds brings a lot to the party. Without taking such things into account, simple linear causality, as practiced in the “hard” sciences, is not likely to be helpful. A basic course in research design taught by a psychology department will hammer home ideas such as regression to the mean, the importance of control groups, random sampling, statistical confidence intervals, and the role of chance. These concerns may reflect the untidy nature of psychological science, but they also offer the student precisely what she needs when facing contentious claims.
Learning these techniques is no guarantee they will be applied appropriately. Many years ago I had a student who performed extremely well in my research methods course. She was consistently at the top of her class. When the course was over, she came to see me in my office, thanked me for an interesting class, and informed me that she was a fundamentalist Christian. She basically told me, “I learned everything you said to do when faced with unsupported conclusions, illogical arguments, and supernatural accounts for natural phenomena. I simply applied what you taught us on all the classroom examples and examinations. I gave you everything you wanted to hear. Now that the course is over, I’m going back to who I am and what I believe.” She smiled broadly and shook my hand and left with her A average and honors degree in psychology. I told her then that I appreciated her honesty, and I still do today. Likewise, any of our A-level students can finish their reading assignments on logical reasoning, go back to their dormitory and listen uncritically, even supportively, as one of their room-mates goes on about a psychic experience she’s just had. In short, a rigorous education grounded in scientific method does not provide foolproof immunity against uncritical listening and irrational beliefs. But, all things considered, I wish more people had such an education.
IT’S ONLY A THEORY
The term
theory
has gotten an increasingly bad name in the popular press. What should be a grand compliment has become a damning indictment. The creationists now point out with glee that evolution is
only
a theory. In Cobb Country, Georgia, the board of education insists on placing stickers in biology textbooks reminding students and teachers alike that evolution is not a fact; it is
only
a theory. To them, that means, “You don’t really know for sure. And if you don’t really know, you should be teaching alternatives (such as intelligent design) side by side. The two should have equal footing since they are both merely possibilities.” Actually, as Richard Dawkins pointed out in the May 21, 2005,
London Times
, creationists are saying even more than that. They argue that whenever any ignorance or gap in the fossil record can be revealed, the winner by default is intelligent design.
To discredit something as merely being a theory misunderstands what science is all about. Calling something a “theory” is, in fact, quite a compliment. It means the possibility has been stated in such a way that it can be tested. Two things can happen when you test a theory: The evidence we gather may support the theory. On the other hand, the evidence we gather may refute it. Theories stand or fall on the available evidence. You cannot cling to them for sentimental reasons or by faith alone. Evolution by natural selection is stated in such a way that evidence can disconfirm it. This is no small thing. It is like doing a high-wire act without a net. If fossilized remains of rabbits are found in a pre-Cambrian stratum, then evolution is wrong. It must be consistent with the fossil record. That is what being a theory is all about.
Creationism, aka intelligent design, is not a theory. It is a belief. The bumper sticker says it all: “The Bible says it; I believe it; That settles it.” There is a name for this approach to knowledge. It is called
fideism
. It is an aggressive irrationality, a refusal to discuss or justify statements of belief. Many children go through a stage in which they use the word
because
as if it were a reason. “Why?” “Because.” Needless to say, most children successfully grow past this irrational early stage of cognitive development. Obviously, not all of them do.
The next time you witness or participate in a debate with a creationist, ask him what kind of evidence it would take to refute intelligent design. The truth is, there is none. It cannot (and will not) be refuted in the mind of a creationist. That alone tells you why intelligent design is not a theory. Creationists may see that as a strength, but it is just the opposite. In any case, it is precisely the reason that intelligent design has no place, no matter what your local board of education says, in the curriculum of a science class.
I teach a fourth-year class in my university that is termed a “capping course,” that is, an attempt to summarize or integrate much of what has gone on for the past eight semesters. If the process has gone well, my department would like to have instilled more than a collection of facts. I use a take-home exam in this course rather than the usual fact-based, multiple-choice format. I find it amusing that the same students who decry multiple-choice exams often do much better on them than they do on open-ended essay exams. At least the ones I give.
In this case, I wrote a special question that I will probably have reused several times by the time you read this. I thought it might be a particularly good question when I created it, but I had no idea how well it would discriminate between good and bad students. That, of course, is the ultimate criterion for the success of any exam question.
The question asked them to imagine a patient with a puzzling phobia. Her family doctor calls in two consultants. The first, an evolutionary psychologist, suggests that her phobia reflects what is called a “prepared association”: an evolutionary predisposition for certain types of Pavlovian conditioning that would manifest itself as a phobic reaction. That our ancestors’ adaptations would affect our present-day thoughts and actions is the essential tenet of evolutionary psychology. The second consultant in my hypothetical scenario is the ringer. He examines the patient and reports that she experienced, in a previous life, some trauma at the hands of her father and had carried forward this trauma to her present life. If there is any doubt in the reader’s mind, past lives may be all the rage in some parts of popular culture, but they have absolutely no standing in scientific psychology. You may not know that if you watch reruns of
The X-Files
or
Medium
, but after four years of university education and a major in psychology, you should recognize this kind of nonsense when you see it.
A shockingly large portion of students did not. Far too many of them treated this supernatural account as if it were any other theoretical viewpoint within psychology and gave it serious consideration. Curiously, a number of students described the reference to “past lives” as a Freudian account, which it assuredly is not. But most troubling was the position expressed in about 20 percent of the papers: that the two accounts, Darwin and past lives, had equal standing. As one student put it, “Past lives is just a theory, like Darwin.”
In grading her paper, I underlined that sentence in red and, might it not potentially cause her embarrassment, I would have posted the sentence on my office door. It goes to the heart of what is wrong with science education and certainly, in this case, underscores one of the failures of a four-year education in my department. I wrote the offending student a memo but could barely do justice to the magnitude of her error. No, I explained to her, so-called past lives is not “just a theory” at all, and the idea is in no way comparable to the theory of evolution by natural selection.
The biggest problem, again, is the word
theory
. Suffice it to say that to the average person with no scientific training (which this student was not),
theory
is synonymous with
hunch
. But there is a big difference between everyday or folk use of the term and what it means within science. For something to have been elevated to the status of theory, it has undergone extensive critical attention and formal testing. It reflects a trail of intellectual activity of the highest order. In fact, it is the very opposite of a hunch. So, yes, Darwin’s view of evolution by natural selection
is
a theory. And one of the most successful ones in all of science. In fact, it is the very cornerstone of biology. What
isn’t
a theory is the belief in past lives. To dignify it with the status of theory would be to suggest that it has been stated in a manner that leads to hypothesis testing, much less that there has been one shred of empirical evidence to lend it support.