Defending Wishful Thinking in Science

by Jerry A. Coyne, Ph.D
[REPRINT]

On June 25 I took issue with a piece by Scientific American columnist John Horgan. Horgan attacked biological determinism on the grounds that it was both wrong (empirically and morally!) and robbed us of free will:

Biological determinism is a blight on science. It implies that the way things are is the way they must be. We have less choice in how we live our lives than we think we do. This position is wrong, both empirically and morally.

I responded that truth is truth, and that Horgan’s view that all biological determinism—including studies of evolutionary psychology—is “pseudoscientific ideology,” is simply silly. Clearly at least some of our modern behaviors—most notably sexual behavior—reflect selection pressures on our ancestors.

At any rate, Horgan has responded to my critique on his website, in a piece called “In defense of wishful thinking.“ Horgan’s defense is this: “Actually, science itself demonstrates that our hopes and fears about reality often shape it.”

He gives some examples of how “hopes and fears about reality” change our behavior:

• The placebo effect: if patients think a pill or spray will work, even if it’s completely inert, it will work to some degree.


• Denigrating ethnicity or gender adversely effects the performance of members of the maligned groups. Women do better on math tests when they’re told in advance that both men and women score equally well on such tests.


• Students who believe that “wars are inevitable because human beings are naturally aggressive” tend to be less involved in disarmament and antiwar activities. (Horgan uses this result to argue against the idea that war stems from the innate aggression of males. I agree with Horgan in part, for war doesn’t necessarily reflect individual aggression, but the machinations and ambitions of politicians—and many soldiers are conscripted unwillingly.) Nevertheless, evolved male aggression is a viable hypothesis, supported by evidence that the hormones associated with human “maleness” induce aggressive behavior. It’s also a reasonable hypothesis that this connection was created by natural selection in our distant past. We may not like this, but that doesn’t falsify it a priori.


• Denying free will has adverse consequences. As Horgan notes,
  

  A recent experiment shows that belief in free will has measurable consequences. The psychologists Kathleen Vohs and Jonathan Schooler asked subjects to read a passage by Francis Crick , co-discoverer of the double helix, that casts doubt on free will. Crick wrote in The Astonishing Hypothesis (Charles Schribner’s Sons, 1993) that “although we appear to have free will, in fact, our choices have already been predetermined for us and we cannot change that.” Subjects who read this passage were more likely to cheat on a test than control subjects who read a passage about brain science that did not mention free will. Mere exposure to the idea that we are not really responsible for our actions, it seems, can make us behave badly.

Note: most of these students probably conceive of free will as a “ghost in the machine,” not in the way that most compatibilist philosophers conceive of it.

To me, none of these assertions pose the slightest problem for biological determinism. Let us first dispose of the “problem” that scientific truths may sometimes induce adverse behavior. That may be the case, but empirically-determined truths do that all the time. A woman who gets proof that her spouse is cheating may poison him, but that doesn’t change the facts. We always must worry about the consequences of scientific truths, but let us not argue that things are less likely to be true because of their consequences. I know that I am going to die, and I really don’t like that truth, but it doesn’t make me deny the fact or embrace the notion of an afterlife.

More important, biological determinism reflects not just our genetic endowment, but our environments (both physical and social), and the interactions between our genes and our environments. As a biological determinist, I believe that these factors completely explain our behaviors. All of the observations mentioned above above are simply environmental interventions that affect our behaviors. That they do so is not an argument against biological determinism, any more telling than the argument that when you hit someone on the head, he becomes unconscious.

Horgan then takes up “free will” again. (I’ve previously given my notion of free will, which involves our ability to really make choices; that is, rerun a situation and you could just as well have chosen otherwise.) Horgan, however, ascribes to Dennett’s notion of free will, one that I’ve previously discussed:

(Horgan): This finding supports a sensible defense of free will mounted by the philosopher Daniel Dennett in his 2003 book Freedom Evolves (Viking Adult, 2003). Dennett argues, first, that free will is “not what tradition declares it to be: a God-like power to exempt oneself from the causal fabric of the physical world.” Free will, he contends, is an emergent property of the brain, like consciousness, that allows us to perceive, mull over and act on choices; in fact, choice, or even freedom, are reasonable synonyms for free will. Dennett calls free will “an evolved creation of human activity and beliefs” that humanity acquired recently as a consequence of language and culture as well as consciousness. Our free will grows along with our knowledge, material well-being and political freedom. Dennett’s most subtle, profound point is that free will is both an “objective phenomenon” and dependent on our belief in and perception of it.

In other words, the more we value and believe in free will, freedom and choices, the more we actually have. This is both wishful thinking and an objective, empirical truth. Wishful thinking works!

I do like Dennett’s pithy definition of “traditional” free will, but I’m not on board with either Dan’s solution or Horgan’s agreement with it. What they are saying is that the mere appearance of choice (an appearance that Dennett sees as reaching its acme, via evolution, in the complex ruminations of the human brain) is the same as “free will.” (As I remember Dan’s discussion in Freedom Evolves, he doesn’t think that any animals have free will.)

To be frank, I regard these conceptions of free will as attempts to evade the depressing fact that we really don’t make choices—that, with perhaps some quantum-induced but irrelevant exceptions—our choices have already been made before we think we’ve made them. (There is, of course, some neurological evidence for this.) Yes, if you define free will as the appearance of choice—that a woman stands before a gelato counter and appears to ruminate about which flavor she wants—and that human choice involves more complex “calculations” than that of, say, a bacterium (“Hmm. . . . I had the lemon last week. I’ll try the blackcurrant now”), then yes, we have free will. But that’s a definitional ploy, meant to keep us from thinking about the inescapable fact that such decisions are “made” long before we think we make them, and to preserve the status of humans as unique and morally responsible animals.

Horgan’s assertion that the more we think we have free will, the more free will we have, is simply wrong. We don’t have free will, at least not in the way everyone thinks we do. We are biologically determined creatures, with “biology” conceived broadly as “genes + environments + gene/environment interactions). Our brains—and therefore our choices—are as biologically determined as are our livers or kidneys. The appearance of choice is no more “real choice” than the “appearance” of a Western movie town, with its thin storefront facades buttressed from behind, is identical to a real town. Biological determinism is a fact, and Horgan should deal with it. But let no one think that biological determinism means that our behavior isn’t influenced by our environments.



A facade: the exterior of the Cleaver house, where Beaver, June, Ward, and Wally supposedly lived.