Steven Pinker is an experimental psychologist and one of the world’s foremost writers on language, mind, and human nature. Currently Johnstone Family Professor of Psychology at Harvard University, Pinker has also taught at Stanford and MIT. His research on vision, language, and social relations has won prizes from the National Academy of Sciences, the Royal Institution of Great Britain, the Cognitive Neuroscience Society, and the American Psychological Association. He has also received eight honorary doctorates, several teaching awards at MIT and Harvard, and numerous prizes for his books The Language Instinct, How the Mind Works, The Blank Slate, and The Better Angels of Our Nature. He is Chair of the Usage Panel of the American Heritage Dictionary, and often writes for The New York Times, Time, and other publications. He has been named Humanist of the Year, Prospect magazine’s “The World’s Top 100 Public Intellectuals,” Foreign Policy’s “100 Global Thinkers,” and Time magazine’s “The 100 Most Influential People in the World Today.”
Question: What is free will?
Steven Pinker: I don’t believe there’s such a thing as free will in the sense of a ghost and a machine, a spirit or a soul that somehow reads the TV screen of the senses and pushes buttons and pulls the levers of behavior. There’s no sense that we can make of that. I think we are . . . Our behavior is the product of physical processes in the brain. On the other hand, when you have a brain that consists of one hundred billion neurons connected by one hundred trillion synopses, there is a vast amount of complexity. That means that human choices will not be predictable in any simple way from the stimuli that I’ve hinged on beforehand. We also know that that brain is set up so that there are at least two kinds of behavior. There’s what happens when I shine a light in your eye and your iris contracts, or I hit your knee with a hammer and your leg jerks upward. We also know that there’s a part of the brain that does things like choose what to have for dinner; whether to order chocolate or vanilla ice cream; how to move the next chess people; whether to pick up the paper or put it down. That is very different from your iris closing when I shine a light in your eye. It’s that second kind of behavior – one that engages vast amounts of the brain, particularly the frontal lobes, that incorporates an enormous amount of information in the causation of the behavior that has some mental model of the world that can predict the consequences of possible behavior and select them on the basis of those consequences. All of those things carve out the realm of behavior that we call free will, which is useful to distinguish from brute involuntary reflexes, but which doesn’t necessarily have to involve some mysterious soul.