Straw man. In what way would free will invalidate the study of human behaviour? That the brain inherently retains a mechanism to resist its internal biases, however strong, does not prevent research into these biases. That the probability of a particular response never rises to 1, or falls to 0, does not stop you studying it. In fact, even without free will, the brain may still ignore any strength of bias, and respond or not respond regardless of whatever the circumstances driving it. A few molecules of GABA diffusing in the wrong direction and suddenly the brain comes down on the wrong side of a tipping point and the predicted behaviour goes *poof*. Free will suggests that we cannot study ourselves about as much as Brownian motion does.
Nope, not a straw man. The counter-arguments you bring up all rely on random processes, not willful ones. In the aggregate, random processes are quite predictable (ask Las Vegas).
1) Quite a lot of quantum behaviour has no causes; science still studies quantum behaviour. Regardless of whether free will exists or not, not all psychological behaviours will have precise causes because of the stochastic nature of many neurophysiological mechanisms. Of course, psychology no more needs precise causes that QCD needs a mechanism to predict particle decay.
At the level of analysis we are looking at (human behavior), quantum effects are irrelevant; even if we look at your "few molecules of GABA", we are orders of magnitude away from worrying about quantum fluctuations. At our level of analysis, we are perfectly justified in looking for causes. And "precise causes" is an interesting phrase...we are looking for actual causes. This means we are behaving quite differently than, say, a court of law looking for liability. We are not looking for "the cause" of a behavior, but for all the factors which play a causal role. Looking at, say, perceptual fields, where we can have electrodes measuring single neurons and their immediate neighbors, and see exitatory and inhibitory signals to each other as well as signals on down the optic nerve. The extraordinarily complex nature of nerve interaction (thousands of synapses for a given neuron!) may render it
practically impossible to understand, but certainly not impossible to understand in principle. (Oh, and of course, we have many different levels of analysis to work with. As Corey will confirm, it is quite useful to look at the level of the behaving organism in its environment. Rather than trying to reduce our behavior to the actions of quarks, it is pragmatic to actually study...our behavior.)
Free will, however, is assumed to be neither determined nor random, but willful. (I reviewed an intro textbook where the author, a prominent physiological psychologist, had written that [paraphrasing] "when sufficient neurotransmitters have stimulated the dendrites of a neuron, it decides to send an action potential down its axon..." The key phrase here is "it decides"; it implied that the neuron, under the exact same circumstances, could have decided not to. If that were the case, there would be no systematic neuron function to study, and there would be no prominent physiological psychologists. Oh...they changed the wording before publication.)
2) Science is constrained to provide naturalistic explanations for phenomena, and not explanations derived from what we already know. Any putative mechanism for true free-will will be required to demonstrate its validity same as everything else. That we know of no such mechanism is not evidence that there is no mechanism. Claiming that the existence of any such mechanism invalidates science is not only an argument from adverse consequences, it is wrong.
I am not claiming that the existence of such a mechanism invalidates science; I am claiming that the assumption of such a phenomenon is a dead end. We assume "no free will" because free will is neither random, which we could study, nor determined, which we could study. If our assumption is wrong, it will have to be abandoned. Thus far, it holds up nicely.
In order to argue for free will, people in this thread and others are being forced to re-define the concept. A free will that allows you to always choose what determinism would have forced you to choose anyway is not our understanding of free will (and is superfluous, and has no explanatory power). A free will that is unconscious is not our understanding of free will. Our "free will" is seen as a conscious director of our behavior, free from influences in our environment (see the "choosing not to eat" example). In casual observation, it would be impossible to distinguish true free will from simple ignorance of causal variables. Experimentally, we can manipulate variables and demonstrate changes in behavior without conscious awareness. That is, we know that at least some of our behavior is determined and not freely chosen. So, absolute free will, as it has been traditionally defined, is out. We are left, as I said, with a "free will of the gaps" that is shrinking by the day. The "at least some" gets larger every day. Our struggle to preserve some sort of coherent concept of free will, and the contortions we go through to hold on to that concept, recall the same dismay that we were not the center of the universe, nor god's special creation. The creationists are still fighting that one; I don't expect the defenders of "free will" to go gentle into that dark night anytime soon.
No. Just not unanswerable.
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