“Is this killing a sin?” — a question the model does not ask

Asked point-blank whether a killing is a sin, or a war lawful, the engine refuses. Not out of caution: those predicates are not declared, and the model is not allowed to make them up.

A traveler has killed a robber. Under Thomas Aquinas — is this killing a sin? Is this war lawful?

There is no single predicate “is this killing a sin” or “is this war lawful” in the applied model, and I should not invent one. Let me put the question to the engine exactly as you asked it, so you can see what it does with a question the text does not ask.

Refused: the predicate is not declared. That is neither “yes” nor “no”. Let me search in your words for what the text does say.

The nearest real things are defensio_licita — whether a defence is licit — and bellum_iustum, which needs the prince's authority, a just cause and a right intention together. Those I can answer, with your facts. What I will not do is stamp “sin” or “lawful war” on a case the model does not ask that way.