Turtles All the Way Up

I have defended free will and criticized Sapolsky before, and now this NY Review of Books review does a better job:

After spending most of the twentieth century watching birds, the Harvard ornithologist and evolutionary biologist Ernst Mayr concluded that they were rote little machines. He wrote in 1988 that birds and other animals are no more purposeful than computers: they behave as they’re programmed to. If you’ve ever seen a bird, you might find that surprising: they certainly look purposeful as they seek out unsuspecting rodents to swoop down upon, ferry worms to their irksome offspring, and produce miniature versions of the Beijing Olympic stadium.

Even more remarkable than Mayr’s claim itself is the fact that it purports to represent a scientific view of things. For one thing, programmed by whom? Mayr’s answer was that birds and other creatures were programmed by natural selection via genetics: natural selection favors genetic “behavior program[s]” that maximize fitness, for instance by ensuring an “instantaneous correct reaction to a potential food source, to a potential enemy, or to a potential mate.” Mayr didn’t justify his belief in behavior programs other than by claiming that this was the only legitimate possibility: the alternatives were “supernaturalistic.” He wasn’t even going to “waste time showing how wrong” they were. Mayr’s genetic behavior program, in other words, was axiomatic; we might call it a dogma.

Robert Sapolsky, a neuroscientiest and primatologist at Stanford, carries the argument further in his new book, Determined: A Science of Life Without Free Will. It’s not just other animals that are deterministic machines, he says, but humans. Embracing a scientific worldview, for Sapolsky, means accepting that there’s no free will. Every development, including every action of living beings, follows inexorably from the previous state of things: “We are nothing more or less than the cumulative biological and environmental luck, over which we had no control, that has brought us to any moment.”

In case you think this is a straw man attack, Biology professor Jerry Coyne responds:

Science can’t prove there’s no free will because the question of free will is not a scientific question but a philosophical one. To misrepresent it as a scientific question is a prime example of scientism—extending the claims of science beyond its bounds. Here’s another from Sapolsky’s final chapter: “What the science in this book ultimately teaches is that there is no meaning.” This might sound like the opposite of saying that science shows there’s a divine intelligence behind the world-machine, but it’s the direct descendant of that earlier claim, and comes to the same evacuation of meaning and agency from the mortal world. This isn’t a scientific proposition. It remains what it has been from the beginning: a theology.

This is wrong. One can gather data for and against determinism. If, for example, we found out that people could move objects by thinking about them, that would suggest that there is some nonmaterial brain force that can actually influence events, buttressing (but not “proving”) the case for free will.

This is a head-scratcher. What would psycnokinesis have to do with determinism? Coyne thinks that all mental processes are predetermined, so why would psychokinetic processes, if they exist, also be predetermined?

Ignorance of science. Riskin doesn’t realize that getting evidence for phenomena (e.g., evolution) is very often a step-by step-process: you have an initial hypothesis, and then you either reinforce or reduce the likelihood of its being true with new data. This is a Bayesian approach, though often it’s implicit rather than specified using Bayes’s theorem. You don’t “prove” determinism or free will, you simply gather evidence that makes one of them more likely.

Everyone knows this. Sapolsky merely gathers evidence for processes being 20% determined, and then makes the leap to 100% determined. All free will advocates agree that processes are partially determined.

Coyne's main argument is that if humans do make decisions out of free will, then there is no scientific explanation for what causes those decisions. Therefor he says scientists should reject free will.

Of course there is no scientific explanation for free will. That is the whole point. A free decision is not caused by previous events.

Coyne takes offense at this comment:

I put the “no free will” people in the same basket as solipsist who prove only they exist. My answer is “so what?” An illogical but psychologically satisfying refutation of Berkeley’s claim that nothing exists outside our mind is when Samuel Johnson kicked a rock. I prefer the psychological truth over the logical truth.

Try to live as if there is no free will. Good luck. Try to live as a solipsist. Why even argue it since only you exist.

I do agree that denying free will is pretty much the same as solipsism. Maybe logically defensible, but impossible to live by. Coyne responds by saying "read Sapolsky or Harris or me on why there has to be punishment and reward."

You can read the review to see how all this relates to turtles.