Which of the following psychologists would be most likely to assert that free will is an illusion?

Are you reading this because you chose to? Or are you doing so as a result of forces beyond your control?

After thousands of years of philosophy, theology, argument and meditation on the riddle of free will, I'm not about to solve it for you in this column (sorry). But what I can do is tell you about some thought-provoking experiments by psychologists, which suggest that, regardless of whether we have free will or not, whether we believe we do can have a profound impact on how we behave.

The issue is simple: we all make choices, but could those choices be made otherwise? From a religious perspective it might seem as if a divine being knows all, including knowing in advance what you will choose (so your choices could not be otherwise). Or we can take a physics-based perspective. Everything in the universe has physical causes, and as you are part of the universe, your choices must be caused (so your choices could not be otherwise). In either case, our experience of choosing collides with our faith in a world which makes sense because things have causes.

Consider for a moment how you would research whether a belief in free will affects our behaviour. There's no point comparing the behaviour of people with different fixed philosophical perspectives. You might find that determinists, who believe free will is an illusion and that we are all cogs in a godless universe, behave worse than those who believe we are free to make choices. But you wouldn't know whether this was simply because people who like to cheat and lie become determinists (the "Yes, I lied, but I couldn't help it" excuse).

What we really need is a way of changing people’s beliefs about free will, so that we can track the effects of doing so on their behaviour. Fortunately, in recent years researchers have developed a standard method of doing this. It involves asking subjects to read sections from Francis Crick's book The Astonishing Hypothesis. Crick was one of the co-discoverers of DNA’s double-helix structure, for which he was awarded the Nobel prize. Later in his career he left molecular biology and devoted himself to neuroscience. The hypothesis in question is his belief that our mental life is entirely generated by the physical stuff of the brain. One passage states that neuroscience has killed the idea of free will, an idea that most rational people, including most scientists, now believe is an illusion.

Psychologists have used this section of the book, or sentences taken from it or inspired by it, to induce feelings of determinism in experimental subjects. A typical study asks people to read and think about a series of sentences such as "Science has demonstrated that free will is an illusion”, or "Like everything else in the universe, all human actions follow from prior events and ultimately can be understood in terms of the movement of molecules”.

The effects on study participants are generally compared with those of other people asked to read sentences that assert the existence of free will, such as "I have feelings of regret when I make bad decisions because I know that ultimately I am responsible for my actions", or texts on topics unrelated to free will.

And the results are striking. One study reported that participants who had their belief in free will diminished were more likely to cheat in a maths test. In another, US psychologists reported that people who read Crick’s thoughts on free will said they were less likely to help others.

Bad taste

A follow-up to this study used an ingenious method to test this via aggression to strangers. Participants were told a cover story about helping the experimenter prepare food for a taste test to be taken by a stranger. They were given the results of a supposed food preference questionnaire which indicated that the stranger liked most foods but hated hot food. Participants were also given a jar of hot sauce. The critical measure was how much of the sauce they put into the taste-test food. Putting in less sauce, when they knew that the taster didn't like hot food, meant they scored more highly for what psychologists call "prosociality", or what everyone else calls being nice.

You've guessed it: Participants who had been reading about how they didn't have any free will chose to give more hot sauce to the poor fictional taster – twice as much, in fact, as those who read sentences supporting the idea of freedom of choice and responsibility.

In a recent study carried out at the University of Padova, Italy, researchers recorded the brain activity of participants who had been told to press a button whenever they wanted. This showed that people whose belief in free will had taken a battering thanks to reading Crick's views showed a weaker signal in areas of the brain involved in preparing to move. In another study by the same team, volunteers carried out a series of on-screen tasks designed to test their reaction times, self control and judgement. Those told free will didn't exist were slower, and more likely to go for easier and more automatic courses of action.

This is a young research area. We still need to check that individual results hold up, but taken all together these studies show that our belief in free will isn't just a philosophical abstraction. We are less likely to behave ethically and kindly if our belief in free will is diminished.

This puts an extra burden of responsibility on philosophers, scientists, pundits and journalists who use evidence from psychology or neuroscience experiments to argue that free will is an illusion. We need to be careful about what stories we tell, given what we know about the likely consequences.

Fortunately, the evidence shows that most people have a sense of their individual freedom and responsibility that is resistant to being overturned by neuroscience. Those sentences from Crick's book claim that most scientists believe free will to be an illusion. My guess is that most scientists would want to define what exactly is meant by free will, and to examine the various versions of free will on offer, before they agree whether it is an illusion or not.

If the last few thousands of years have taught us anything, the debate about free will may rumble on and on. But whether the outcome is inevitable or not, these results show that how we think about the way we think could have a profound effect on us, and on others.

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Which of the following psychological approaches is known to emphasize free will?

Which psychological perspective focuses on the idea that people have free will and the ability to control one's own destiny?

Which psychologist is most closely tied to humanism?

Who name is associated with positive psychology?