The Argument against Determinism – A Probabilistic Calculation (Column 176)

Why not present it differently?
First of all, we need to decide what human beings' ability is to reach correct conclusions, regardless of determinism or not.
If our ability is negligible, then of course there is no point in a discussion between us. One can raise this as a plausible possibility, but one that precludes discussion. The whole discussion is conducted on the assumption that we have some reasonable ability to reach conclusions, though not necessarily because the assumption is reasonable, but because otherwise there is no point in discussion.
Someone who reaches the conclusion of determinism will say this – perhaps we are completely stupid, and then my conclusion about determinism is invalid, but so is your conclusion against determinism; if we are not stupid, then my conclusion about determinism is not sawing off any branch.

But it is connected to determinism. If determinism is true, the ability is negligible, and if not – then presumably it is not. You can't decide this without making it depend on determinism.

I wasn't convinced by the claim that in a deterministic world the chance of a correct conclusion is negligible. A brain that drew false conclusions about the world would not survive evolution.

And that itself—how do you know it? That is a conclusion of that same compelled brain.