A posting on another website has provided a defense — against proportionalism — of traditional Church teaching that some acts are intrinsically evil. I would like to provide a similar defense, but describe the situation using terms that come from theological Latin, so as to avoid some of the cloudiness that can come from the use of English. The terminology is well explained in other places, such as here and here, which I rely on. The three terms to bring to mind are malum, peccatum, and culpa.

Malum is a very general term for any kind of evil or disorder — a killing, a death, a misunderstanding, a lack of food, and a car with a flat tire are each instances of malum. (Clearly, Church teaching is going to be focused on the malum that can afflict humans.) Within the word malum itself is no hidden context of blame, or punishment. It is simply a word that describes something that should not be there.

Peccatum is a human action that is a malum. Killing someone, having flu, or dropping toast butter-side down, are each instances of peccatum. Again, there is no necessary context of blame.

Culpa is a peccatum that is morally blameworthy, and requires forgiveness. The peccatum of dropping one's toast is very unlikely to be a culpa, but other kinds of peccatum may well be potential moral transgressions. For Catholics, a serious culpa requires confession.

The Church teaches that some personal acts are intrinsice malum (in English: intrinsically evil) — always seriously malum — in such a way as to always seriously harm the person performing them (and perhaps others as well). These acts can never be freely chosen without performing a culpa.

I will, at first, change the situation stated in the other posting, so as to hopefully make the distinction between malum and culpa a bit clearer:

A married woman, with her children, is in a concentration camp. The children are due to be killed the next day. A guard offers to divert the children away from death, provided the woman agrees to sleep with him. The Church teaches that adultery (sleeping with someone not one's spouse) is intrinsice malum. The question is: If the woman sleeps with the guard, does she necessarily commit a culpa?

The answer (entirely in line with Church teaching) is: not necessarily. The easiest way to see this is to suppose the woman has never been exposed to Christian teaching on this matter, or anything like Christian teaching, and even has been taught the opposite. With such ignorance, there can no question of a culpa.

Yet malum will always still flow from the action. There are various different ways in which malum can occur in the given siutation, even where there has been no culpa: the woman may subsequently have a harder time accepting the truth of Christian teaching, if she should learn it later; she may find it subsequently easier to accept other offers from guards that may be culpa for her; she may become pregnant, and be less able to look after her other children; she may provide (even unintentionally) a bad example for those for whom the same act may be culpa; she may later experience anguish if she learns the truth of what her actions accomplished (even if this learning were to occur post-death).

And we have to accept on faith that the malum of an intrinsice malum occurs, even when we cannot see it. The lack of a culpa does not mean that the malum does not occur. So, there are some kinds of action that are intrinsice malum, but they are not thereby intrinsice culpa.

However, an action that is intrinsice malum can never be freely chosen without it necessarily being a culpa. One can always discuss the circumstances of a particular action, and try to decide if it were freely chosen or not — and the circumstances can range from very clear to very cloudy indeed. But this may do nothing to help illuminate the difference between intrinsice malum and culpa.