It is difficult to find true aphorisms of Thomas Aquinas. He was no rhetorician, his precision and brilliance with language notwithstanding, and so he’s not often good for those ‘one-liners’ that everyone else seems to be able to write. (E.g., Augustine: “If you believe what you like in the gospels, and reject what you don’t like, it is not the gospel you believe in, but yourself.”) Nevertheless, I found a cool page that does its best to collect some quasi-aphorisms from Aquinas. Here is one passage that I liked especially on the nature of weakness, choice, and sin:
Since the act of sin or of virtue is according to choice, and choice is a desire for something previously deliberated about, and deliberation is a kind of inquiry, it is necessary that in every act of virtue or of sin there be a kind of syllogistic deduction. But a temperate and an intemperate person syllogize differently. The same holds for a continent and an incontinent person.
A temperate person is moved only by a rational judgement, using a syllogism of three statements, as:
Fornication should never be committed.
This act is fornication.
Therefore it must not be done.An intemperate person, however, totally follows concupiscence, and likewise uses a syllogism of three statements, as:
Everything pleasurable must be enjoyed.
This act is pleasurable.
Therefore it must be enjoyed.
But a continent and an incontinent person have two moving forces. One is reason, to avoid sin. The other is concupiscence, to commit it. But for the continent person the judgement of reason wins, whereas in the incontinent person the movement of concupiscence wins. Thus each of them uses a syllogism of four statements, but leading to contrary conclusions.
The continent person uses the following syllogism:
No sin must be committed (a judgement of reason).
Everything pleasurable must be enjoyed (what concupiscence presents to his heart).
This is a sin (the victorious judgement of reason).
Therefore this should not be done.
The incontinent person, for whom the judgement of concupiscence prevails, argues this way:
No sin must be committed (a judgement of reason).
Everything pleasurable must be enjoyed (what concupiscence presents to his heart).
This is pleasurable (the victorious judgement of concupiscence).
Therefore it must be enjoyed.Thus the incontinent person has universal, but not particular, knowledge of the issue, since he does not follow the particular judgement of reason but that of concupiscence.
