The free will debate has been going on for millenia and, like most philosophical debates, shows little chance of being settled anytime soon. A significant part of the debate is definitional: what do we mean when we say “free will.” We can argue endlessly about what the term should mean, but it turns out that what most of us actually mean by it is something that can be studied empirically.
For those who argue that what we know about neuroscience is incompatible with free will, predicting what our brain is about to do should reveal the illusory nature of free will, and lead people to reject it. Experimental philosopher Eddy Nahmias at Georgia State University in Atlanta dubs this view “willusionism”. He recently set out to test it.
Nahmias and colleagues borrowed an idea from Harris, and gave 278 people a story describing a future neuroimaging technology that allows perfect prediction of decisions based on a person’s neural activity, recorded in a special skull cap. In this future world, a woman called Jill is fitted with a skull cap for a month, which allows scientists to predict everything she’ll decide and do with 100 per cent accuracy, including how she’ll vote in upcoming elections. To some, the fact that Jill is totally predictable – like the trajectory of balls bouncing around a pool table – is clearly incompatible with her having free will in the first place.
The team found that 92 per cent of participants said that Jill voted of her own free will, contrary to the expectation of the willusionists.
In other words, determinism, even if strictly true, doesn’t preclude most people’s intuitions about free will. But then, if the ability to predict what someone will do doesn’t erase free will, what does?
In another version of story, the scientists didn’t merely predict which way Jill would vote – they also manipulated her choice via the skull cap. With that scenario, most participants said that Jill did not vote of her own free will.
To find out why prediction didn’t impact beliefs about free will but manipulation did, the researchers posed a series of questions about why Jill behaved as she did in the different scenarios, and whether she remained responsible for her behaviour.
They found that even when Jill’s behaviour could be predicted, people still thought she acted on her own reasons, and remained responsible for them. When she was manipulated, she acted on someone else’s reasons and the responsibility was no longer her own.
Most people’s intuitive conception of free will appears to be the freedom to act on one’s own desires, even if those desires are determined by our experiences, our genetics, and the laws of physics. It’s only when one is forced to act on someone else’s desires that free will disappears.
This intuition appears to broadly match the compatibilist understanding of free will held by most philosophers. It isn’t libertarian free will, which sees our will as free from the workings of the universe and, as one of the theodices (one of the defenses against theological problem of evil) is the version typically debated by atheists and religious apologists.
The results of this study match my own intuitions. I’m not convinced that strict determinism is true (mostly due to quantum physics and chaos theory), but I don’t see that as really rescuing libertarian free will, which I find incoherent. Regardless of whether or not the mind lies completely within the brain, its operations will be constrained by its experiences and nature, even if part of that nature is immaterial.
But I do see the term “free will” remaining useful to describe our ability to act on our own desires, and to pragmatically hold people accountable for their choices, with the strong caution that those choices were constrained by their experiences and genetics. There, but for the whims of chance, go any of us.
What is your definition of free will? Do you think we have it? Are you a determinist? If so, do you think determinism rules out free will? What role does responsibility play?