instruere...inlustrare...delectare Disputations

Thursday, November 01, 2012

A nod to the Common Doctor

St. Thomas's article in the Summa Theologiae on "Whether it is lawful to kill a man in self-defense?"has served as the starting point for much of the Church's subsequent thought on the question (not to mention for thinking about the Principle of Double Effect). The body of the article begins:
Nothing hinders one act from having two effects, only one of which is intended, while the other is beside the intention. Now moral acts take their species according to what is intended, and not according to what is beside the intention, since this is accidental as explained above.

Accordingly the act of self-defense may have two effects, one is the saving of one's life, the other is the slaying of the aggressor. Therefore this act, since one's intention is to save one's own life, is not unlawful, seeing that it is natural to everything to keep itself in "being," as far as possible.
Right away we have the curiosity of St. Thomas saying "moral acts take their species according to what is intended." It's curious, because elsewhere (in fact, lots of elsewheres) he says that "an action has its species from its object."

If you want to build your self-defense doctrine on St. Thomas, then, you're going to have to recognize that, although he most certainly writes here of "intention," what he's referring to is not (unless he's contradicting himself) what we mean by "intention" in the traditional "object"/"intention"/"circumstances" framework, but what we mean by "object." In other words, we should read the above as referring to the kind of behavior the defender is choosing, not the reason why he chooses it.

(It may be that, say, in the context St. Thomas was considering the question, there aren't any generic acts of saving one's life that aren't also specific acts of self-defense, so the object and intention of such acts aren't meaningfully distinguishable. But it's probably better to simply admit that even Homer nods, and that it would have been better if St. Thomas hadn't used "intention" here.)