Three things to say about that. And I know Kant already showed that the Determinism argument fails (in his ANTINOMIES)
1) If there is no free will there is no mind or rationality
"
man acts from judgment, because by his apprehensive power he judges that something should be avoided or sought. But because this judgment, in the case of some particular act, is not from a
natural instinct, but from some act of comparison in the reason, therefore he acts from free judgment and retains the power of being inclined to various things. For reason in contingent matters may follow opposite courses, as we see in dialectic syllogisms and rhetorical arguments. Now particular operations are
contingent, and therefore in such matters the judgment of reason may follow opposite courses, and is not determinate to one. And forasmuch as
man is rational is it
necessary that
man have a
free-will."
2) One could not have the idea even of free will without a free will
3) It makes the most large things in civilization incomprehensible
Man has
free-will: otherwise counsels, exhortations, commands, prohibitions, rewards, and punishments would be in vain.
Why would someone , whether Jesus or Socrates or Kant, deterministically be driven to state utter falsehoods.
I tell you, after long investigation, you are denying REASON before you deny Will. Because will follows reason.