Determinism means that all events, including thoughts and actions, must necessarily proceed as determined. This is not a matter of choice, but the state and condition of the system. Whatever has been determined to happen must happen, being determined to happen, it inevitably will happen.
And every time you decide to have dinner in a restaurant, the "state and condition of the system" will determine that you must make a choice from the menu. So, being determined to happen, your choosing inevitably will happen.
At some point I hope you will realize that determinism doesn't actually change anything.
Not according to the given terms and conditions of determinism, where whatever you do you must do.
That's what I just said. Choosing happens to be one of those things that you do, and you must do it. When you decide to eat at a restaurant, you will have no choice but to choose something from the menu of alternate possibilities.
You do it without realizing that you must because the impulse or drive comes from within the unconscious processes of the brain.
Actually, you will be conscious of the fact that you are in a restaurant, and you will be conscious of the menu, and you will be conscious of any reasoning that deterministically leads you to your choice. Unless you're a sleepwalker, the fact that the waiter places the dinner that you ordered on the table in front of you, will not come as a surprise.
Granted that there will be layers of unconscious processing that construct each conscious experience, all you will have to work with in any practical sense is those conscious experiences along the way, the thoughts and feelings that rose to awareness as choosing took place.
But keep in mind that those layers of unconscious processing were motivated and directed by a decision that you were fully conscious of, your choice to have dinner at a restaurant. That's why you are not surprised by the memory that you drove to the restaurant, walked in, picked up the menu, considered your options, decided what you will have for dinner, and conveyed your will to the waiter. "I will have the Chef Salad, please."
Oh, and there was no absence of the "sense of must". Your desire to eat out rather than cooking something yourself necessitated your going to the restaurant, which necessitated you confronting the menu, which necessitated you considering your options, which necessitated you decision to order the Chef Salad. If we were to ask you why you did any one of those things, you would be able to tell us the prior events that led you to that specific event.
All of your thoughts and actions were reliably caused by your prior thoughts and actions. Your behavior was fully deterministic.
Semantics, the study of the meaning of our words and concepts, ain't trivial. It is the source of all meaning.
Given the condition that all actions including thoughts are fixed by antecedents, 'would not' is equivalent to 'could not,' and makes no difference to outcome.
I've shown many times now that the assumption that there is no difference between we "would" do and what we "could" do leads to nonsense, due to the destruction of meaning.
For example:
Waiter (a hard determinist): "What will you have for dinner tonight, sir?"
Customer (hungry): "Gee, I don't know. What are my possibilities?"
Waiter: "Because we live in a deterministic universe, there is only one thing that you can order".
Customer: "Oh. That's disappointing. But, okay then, what is that one thing that I can order?".
Waiter: "I don't know."
The customer must (a) choose between a single possibility (which is itself impossible) and (b) do so without even knowing what that possibility is!
The loss of the correct meaning of "can" by conflating it with "will" leads to nonsense.
How do you think determinism works?
Same as you. "Whatever happens must necessarily happen, therefore will happen. - DBT"
That anyone can do anything at any given moment in time?
Don't be silly. There are many things that we cannot do. But there are also many things that we can do. One of the things, that we definitely can do, is choose from a restaurant menu what we will order for dinner. And this is consistent with determinism, because it definitely does happen, therefore it necessarily must happen.
If the condition, 'no alternate actions are possible' is unpalatable to the rational mind, so is determinism because that is precisely what determinism means.
Alternate actions are possible. Determinism simply asserts that only one of those possibilities will actually happen. And that comports with our observation that, despite the many dinners on the restaurant menu, only one of them was ordered.
There is no uncertainty in a deterministic system, that is, apart from minds that lack the necessary information, an uncertainty of perception and knowledge of the state of the system, an uncertainty of mind that is determined by the system as it evolves without deviation from prior to current and future states.
I think what you just said is that there IS uncertainty within a deterministic system, and that uncertainty is found in our own human minds, which exist deterministically within a deterministic system. When there is uncertainty, it will, like choosing, be causally inevitable from any prior point in time.
Determinism doesn't actually change anything.
Or are we talking about Libertarian Free Will?
No. We're talking about what determinism does and does not logically imply. Libertarians, as I understand it, consider determinism to be false. But I defend rational determinism, which you've seen me do throughout this discussion. And I also defend the rational, operational definition of free will, which is simply a choice we make for ourselves while free of coercion and undue influence. Both concepts, when correctly understood, are compatible with each other.