If I have understood you, you are saying that freedom consists in acting, or believing, for reasons. It is the very determinative character of reasons that constitutes freedom. — John
Actually, I never thought about
defining freedom in that way. I merely accept the idea that freedom requires the ability to have done otherwise in the circumstances in which one acted (i.e. I am accepting the weak version of the PAP). And I am questioning the strange and -- I would argue, incoherent -- construal that the determinist makes of the notion of an agent's "circumstances" such that anything that occurs within her own body constitutes for her such "circumstances". This confused notion gives rise to what I have termed the
strong version of the PAP, which I reject. It depends on one conceiving the agent as something essentially disembodied. This strong version of the PAP often seems to be tacitly endorsed by both the compatibilists and the incompatibilists in a large portion of the literature on free will (with many notable exceptions).
What is "historically necessary" for an agent is, then, determined by antecedent worldly events; like the bus might be predetermined to be late. So it will be historically determined that the agent will not catch the bus. But then, she might do any of a range of other things.
Yes, what it is historically necessary that an agent will do is relative to the circumstances of her action. It consists in what it is, in those circumstances, that it is not up to her to prevent anymore (or ever). Hence, the range of what it is historically necessary that will occur increases over time (from my perspective, say) since the range of the possibilities for action that are open to me diminishes over time (in other words: I settle things over time); and this range isn't the same for me as it is for you, since different persons don't have the same powers and opportunities.
However it is a strong physicalist claim that whatever she does will ultimately be determined by neural activity.
Yes. It is a reductionist claim that goes beyond the claim that she is materially constituted and that her bodily motions (as they may be described in purely physical terms) are governed by the laws of physics. The reductionist claim goes further than this claim about material constitution since it also presupposes that actions, in a sense, supervene on bodily motions in such a way that whatever determines bodily motions also determines actions.
The questions then become: is she determined by the micro-physical brain activity or is she determined by her reasons?
At this stage in the argument, I think the compatibilist will rightly point out that the question sets up a false dichotomy. The microphysical brain activity settles what bodily motions will occur
and the person deliberates and choses what she will do. The former may be part of a story about what it is about the person's neurophysiology that enables her powers to do the latter (i.e. deliberate and act).
Are the reasons only a post hoc rationalization of her actions or is there a genuine 'top down' effect; a kind of 'formal causation' that is itself not reducible to micro-physical determination?
I think downward causation is ubiquitous in nature, and it isn't mysterious. Pretty much all irreducible explanations of anything that occurs in nature, and that refer to the powers or dispositions of things, are of that kind. The availability of those explanations, as genuine explanations and not mere "rationalizations", is what is contested by reductionists and eliminative materialists. (To be fair, the reductionist may grant that there are such genuine explanations at the higher level, but question their independence from explanations of what occurs at the lower level).
For sure, explanations of the actions of human agents are, for the most part, rationalizing explanations. But they are not mere (i.e. illusory or false) rationalizations but rather genuine explanations as to why someone acted in one way rather than another way. For instance, I didn't go to the supermarket because I was informed that it was closed. This genuinely explains why I didn't go. It would have been irrational for me to go (because I need to buy some milk, say) while I knew that it was closed. A close examination of what went on in my brain could explain how I was able to reason that it was useless for me to go, but whatever this inquiry discloses doesn't compete with the rational explanation of my action. It merely changes the subject of the inquiry.
Can it make sense to say that she is determined by both, and if we want to say that, how do we understand the relationship between causal and rational determination?
Rational determination is a species of causation. It explains things that occur at a higher, more relevant, level of the activity of human beings. It is an inquiry that is concerned more about their intelligible
actions rather than being concerned about the etiology of their "raw" bodily motions, or about the physiological enablements of their cognitive abilities. Those three different modes of inquiry are possible, and compatible, but they have three different topics.
It doesn't seem logically coherent to claim that any kind of genuinely efficacious formal rational determination of action or belief could be compatible with a rigid micro-physical determinism, and that is why I said that it could only be compatible with micro-physical indeterminism, because that would allow for genuine novelty and creativity.
This seems incoherent only if you endorse (maybe inchoately) a contentious metaphysical doctrine such as eliminative materialism and can't allow for there being consistent explanations of what happens at different levels of organization/description. Those may be explantations that have different topics altogether. Though, as is the case for the neurophysiological explanations of our cognitive
powers (which need not be reductive explanations), some constraints on our abilities are thereby disclosed -- as are explanations of some of our irrational actions, or habitual cognitive biases -- but they are constraints that fall short from determining our
actions, in most cases, or so am I prepared to argue.