According to rhetoric

I’m not sure I understood the question. But think of an atheist who encounters an argument that proves to him the existence of God. If the argument is logical, then he essentially discovers that he already believed in it before but was unaware of it. For example, the physico-theological argument that the world is complex and that a complex thing did not come into being on its own. If these two assumptions are acceptable to you, then you are already an implicit and unconscious believer in God. But if I tell you that without God there is no valid and binding morality, you can logically argue that if so then there really is no morality. But you might suddenly catch yourself saying that it is impossible that morality is not valid and therefore it is clear that God does in fact exist. This is already a kind of rhetorical persuasion. It can also be translated into logic, and I dealt with this at length in my first published book, The Fourth Conversation.