So I ask again: how is an alternate choice or action possible in the face of inevitability? Which means everything that happens within a deterministic system, happens necessarily, inevitably, implacably.
For the hundredth time: Because stuff in a deterministic system does NOT happen NECESSARILY. It happens CONTINGENTLY. (And I don’t care if Marvin Edwards endorsed yoiur version of physical necessity — I’m not Marvin Edwards. I recognize only LOGICAL necessity.)
Necessary truths are confined to those propositions that are true at all (logically) possible worlds, and false at no (logically) possible world.
“Triangles have three sides” is a NECESSARY truth — true at all possible worlds. It CANNOT be false.
“Today I picked Coke over Pepsi” is a CONTINGENT truth — true at some possible worlds, false at others. This just MEANS, as a matter of logic, that is possible for me to have picked Pepsi over Coke, even though in fact I picked Coke. And it will always remain true, even after the fact, that I COULD HAVE picked Pepsi, even though I picked Coke.
Humans in a deterministic system receive deterministic inputs that present an array of OPTIONS. All those options are fully within our power to choose. I chose Coke over Pepsi, but nothing — certainly not the invisible beast Hard Determinism — was staying my hand from picking Pepsi.
Since I can imagine a world in which I picked Pepsi without logical contradiction, my choosing Coke is by definition CONTINGENT — could have been otherwise, and WOULD HAVE been otherwise, under slightly different antecedent conditions.
Gravity operates universally and the same without known exception, but gravity is still a CONTINGENT truth about the world, because one can imagine, without logical contradiction, a world in which things fall up. So gravity is true at some possible worlds and false at others.
When I output the choice “Coke,” I am PART OF the deterministic system, and I, and I alone, deterministically output “Coke” as the end of a deterministic chain. I NEED determinism to be true in order to that, or anything, because otherwise none of my choices would be reliable.
Finallly, and to repeat yet again, this business about “you could not have done other than what you did,” stated after the fact, is a red herring, because there is only one time line, one history. This means that “could not have done otherwise” collapses to, “did not do otherwise,” and that is simply — compatibilism.
Because if we could replay the history of the world right up the the present moment, the EXACT history of the world, right up the present moment, and I still pick Coke — great!
Why would I do otherwise? That is what I WANTED to do, at that time, under those conditions. Nothing in this experiment, if it hypothetically could be run, would empirically or logically show that I HAD TO pick Coke.
Of course, I have explained all this, many times.