Largely due to the popular allegation that contemporary science has uncovered indeterminism in the deepest known levels of physical reality, the debate as to whether humans have moral freedom, the sort of freedom on which moral responsibility depends, has put aside to some extent the traditional worry over whether determinism is true. As I argue in this paper, however, there are powerful proofs for both chronological determinism and necessitarianism, forms of determinism that pose the most penetrative threat to human moral (...) freedom. My ultimate hope is to show that, despite the robust case against human moral freedom that can be made without even relying on them, chronological determinism and necessitarianism should be regarded with renewed urgency. (shrink)