The 60-Second Aquinas
Lesson
Sin and Human Nature
November 23, 1998
If sin diminishes natural good, as Aquinas determines (ST I-II, Q. 85, Art. 1), then it would seem possible for sin to completely destroy human nature in an individual. Yet, Aquinas determines that this does not happen:
The reason why man inclines to virtue is that he is rational. It is because he is rational that he acts in accordance with reason, and this is to act virtuously. But a man would not be able to sin without his rational nature. Sin cannot then deprive him of it altogether. It follows that his inclination to virtue cannot be entirely destroyed. (ST I-II, Q. 85, Art. 2)
On the one hand, if sin diminishes man’s nature, it would seem that his nature could be completely taken away. But, it is possible, Aquinas says, that this diminution is done by proportion rather than subtraction.
That is, man’s nature could be affected in that half of it is taken with each sin. In this way, man’s nature could be reduced with each sin and yet never disappear.
The true importance of this point lies in Aquinas’ message of hope for even the most heartless of sinners. There is always hope since even the vilest sinner does not completely lose his natural inclination to virtue. Sin serves as an obstacle to that inclination, but it can be overcome.
Explanation of The 60-Second Aquinas Lesson
