A stray thought inspired by TJ White’s reflections on “pure nature.” For Thomas, the human is created in a state of grace, granted “original righteousness” that elevates his capacities above what his nature alone would admit.
the sin of our first parent is the cause of death and all such like defects in human nature, in so far as by the sin of our first parent original justice was taken away, whereby not only were the lower powers of the soul held together under the control of reason, without any disorder whatever, but also the whole body was held together in subjection to the soul, without any defect, as stated in the I, 97, 1. Wherefore, original justice being forfeited through the sin of our first parent; just as human nature was stricken in the soul by the disorder among the powers, as stated above (3; 82, 3), so also it became subject to corruption, by reason of disorder in the body (ST I-II.85.5.c.).
This conceptuality is really helpful for accounting for how the first humans, despite inheriting their bodies from an evolutionary lineage that marked them with dispositions to violence, fornication, and deceit, not to mention death, might still have been constituted in a state of integrity, granted full control over those dispositions and full freedom from death. Absent some distinction between the natural and graced dimensions of humanity’s integral state, is it possible to hold together the biblical picture of a culpable human defection from God into sin and death with evolutionary biology?