Stephen Cave in Aeon:
It is often thought that science has shown that there is no such thing as free will. If all things are bound by the same impersonal cosmic laws, then (the story goes) our paths are no freer than those of rocks tumbling down a hill. But this is wrong. Science is giving us a very powerful and clear way to understand freedom of the will. We have just been looking for it in the wrong place. Instead of using an electron microscope or a brain-scanner, we should go to the zoo. There we will find animals using a wide range of skills that give them options for what to do – skills that we share. These abilities have evolved through natural selection because they are essential for survival: animals need to weigh different factors, explore available options, pursue new alternatives when old strategies don’t work. Together these abilities give all animals, including humans, an entirely natural free will, one that we need precisely because we are not rocks. We are complex organisms actively pursuing our interests in a changing environment. And we are starting to understand the cognitive abilities that underpin this behavioural freedom. Like most evolved capacities, they are a matter of degree. Take, for example, the ability to delay gratification. For a hungry cat, this means being able to hold back from pouncing until it is sure the sparrow is within range and looking the other way. Experimenters measure this ability by testing how long an animal can resist a small treat in return for a larger reward after a delay. Chickens, for example, can do this for six seconds. They can choose whether to wait for the juicier titbit or not – but only if that titbit comes very soon. A chimpanzee, on the other hand, can wait for a cool two minutes – or even up to eight minutes in some experiments. I am guessing that you could manage a lot longer.
The chimpanzee therefore has more options: if a juicier treat became available after six seconds, a chimp would be free to choose whether to wait for it, but a chicken would not. If you can delay gratification even longer, you have still more options: whether to turn down dessert because you are on a diet, or to forego all pleasure in this world in the hope of a heavenly reward. As we start to understand, and learn to measure, the capacities that underlie behavioural freedom, we can begin to put this natural free will on a scale. Paralleling the measurement of intelligence, we could call it the freedom quotient: FQ. Such a scale should give us new insights into the factors that hinder or enhance our efforts to shape our lives. In other words, FQ should tell us how free we are – and how we can become even more so.
More here.