Well, if it's true that "causal determinism is presupposed in the very concept of human action," then it should stay true when I'm talking about causal determinism and human action alone--and I should be able to ask for an explanation.
In other words, how does the fact that people do order soup show that if you load the save file, you're guaranteed the same result? I know it's used as a step in proofs about "free will," but I'm asking about the step, not the proofs. Another proof rebutting some of the people who don't like the first proof isn't an answer.
Wait, are you asking the empirical question, "do human decision-making processes operate in a deterministic fashion"? As far as I can tell, the answer is approximately "yes" (at least at scales typical of ordering food at a restaurant without influence from nondeterministic random-number generators), the aforementioned can-go-either-way philosophers are committed to the opposite answer (or to believing that we're just automata), and the people you really should be asking are the cognitive scientists and neuroscientists. Of which I am neither.
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