Is all immoral action a violation of a duty to someone?

Each of the following propositions is controversial:

1. It is possible to act wrongly without wronging any person.
2. It is possible to wrong oneself.
3. There is a necessarily existing person.

I think (2) and (3) are true. I deny (1), because I think that every wrongdoing wrongs oneself and God.

I shall argue that at least one of (1)-(3) is true. I think the disjunction of (1)-(3) is also controversial, so this result has some interest, I suppose.

The argument for the disjunction of (1)-(3) is based on the following premises:

4. If there are no necessarily existing persons, then it is possible that there is only one person in existence and she acts wrongly.
5. It is not possible to wrong a non-existent person.

Given (4) and (5), the argument is easy. For a reductio, assume that none of (1), (2) and (3) are true. Since (3) is false, it follows from (4) that there is a world w at which is there is only one person in existence and she acts wrongly. By (5) she does not wrong anyone except perhaps herself. But by (1) and (2), she wrongs someone other than herself in w.

I think (5) is very plausible, but (4) needs argument. The argument depends on a simple case. If there are no necessarily existing persons, it is possible that there be only one person in existence and that she be imperfect. (One might think that necessarily if there are imperfect persons, there is a perfect person, but that is only plausible if necessarily there is a perfect person.) Suppose Sally is the one person in existence and she knows that torture of the innocent is wrong and justifiably but falsely believes that by pressing a button she would be torturing an innocent other. She presses the button in order to torture that innocent other for fun. In so doing, she acts against her conscious and clearly does wrong.

Suppose one bites the bullet and says that Sally doesn't do anything wrong. Then by the same token, if I shoot at a distant shape falsely believing it to be the present king of France, but in fact it's just a rosebush, I do not wrong. And that's absurd.

Perhaps, though, (5) can be denied, and it can be insisted that a merely possible person is wronged by Sally. But, still, which possible person is wronged in the Sally scenario? The only at all plausible answer I can think of is: every possible person who could possibly satisfy the description under which Sally intends to torture is wronged. But suppose that Sally also justifiably but falsely believes that humans are reptiles, and she intends to torture an innocent human reptile. Then there is no possible person who fits her description. And the idea that one can wrong impossible persons seems really weird. Certainly it seems more problematic than the disjunction of (1)-(3).

Or maybe instead of wronging possible persons, one can wrong fictional persons. But then writers are in grave moral danger! It seems, for instance, much preferable to suppose one can wrong oneself than to suppose that one can wrong a fictional person.