I think the debate about free will as generally portrayed is a false alternative.
On one hand, the determinists pretend to act as the defenders of science by attributing cause and effect to man's actions. They argue that all effects have causes and in order to be scientific about the whole issue, man's choices have to determined by antecedent causes and that they are determined by one's environment or one's genes.
On the other hand, the indeterminists argue that man's actions have no causes and that there is no reason that explains why a man acts in a particular fashion. Such a view of the debate leads one to think that man is either determined or that he is a freak.
I think this where Ayn Rand stands up and makes herself counted by not getting boxed into any of these alternatives.
Before she addresses the question of determinism or indeterminism, she first looks at the facts. Each of us face a fundamental choice even before one starts thinking about any issue (including the issue of determinism versus free will): the choice to focus or not. Focus doesn’t mean thinking. As Peikoff puts it, it is the "readiness to think". The choice to focus, however, requires effort -- every single time one chooses to activate one's equipment. It requires effort to start up the machinery and sustain it through out any thought process however long or short.
One can easily contrast such a phenomena from the phenomena of mental drift (where one may be reading a lengthy passage and not remember what was said in the preceding paragraphs) or from the phenomena of outright evasion (where one is required to think of some urgent, uncomfortable, pressing matter but puts it off actively by thinking of something less discomforting).
Once the primary choice is made, secondary choices readily follow. For instance, one may choose to activate one's equipment by focusing in a computer shop (primary choice). A person may then prefer to buy a Dell instead of Apple after giving thought to various considerations he might have on his mind (a secondary choice).
In order to unpack the debate on determinism, it is crucial to distinguish between the primary choice and the secondary choice. Given man’s metaphysical nature, the only thing necessitated by his nature that at every moment of his life is that he has the primary choice to think or not to do so. The content of the secondary choices which is made after the primary choice however, is not determined or neccessitated in the same way as the primary choice is.
Although one can ask why one preferred a Dell instead of Apple (a secondary choice), one cannot ask such a question about the primary choice itself. One cannot ask what antecedent factors neccessitated one to be in focus and expend effort. A person chose to be in focus because he wanted to be aware of reality or if a person was partially in focus, it was because he wanted to be partially aware of reality. Even though one accepts a reality oriented approach to life, the choice to focus can neither become automatic (my daily temptation to procrastinate is proof of it) nor can it become neccesitated by antecedent factors. Activating my faculty of thought is an act of choice and requires effort each time.
The debate about free-will should not be a debate about CONTENT, like something versus something else, but should be a debate about PROCESS, like a choice between something being activated and nothing being activated. Put another way, given human nature, the primary choice to think or not is NECCESITATED by antecedent factors (his nature), but the content of the secondary choices itself (whether to buy a Dell or an Apple) is not determined by prior causes.
Free-will is an axiom and therefore any determinist who tries refuting it has to fall into the same trap : reaffirming free will by denying it. When a determinist argues that determinism gives an accurate account of man, what he really means is that he has followed the evidence wherever it has taken him. On the basis of his thinking and evaluation, he beleives he is correct. But how are we to know that his position wasn’t necessitated or pre-determined by factors unknown to him (in his environment or his genes) which only give him the illusion that he has followed the evidence conscientiously? His adjudication of the matter then, however scrupulous, would be irrelevant.
Update: Minor edits
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