Sorry -- I meant that one side of the demarcation line are theorems that we can prove (and prove that we can prove). The other side are two entities -- theorems

Sorry -- I meant that one side of the demarcation line are theorems that we can prove (and prove that we can prove). The other side are two entities -- theorems that are true but not provable, and theorems we don't know enough about to classify. I emphasize that the idea of a demarcation line is itself a matter of debate. Some theorems, by virtue of their unprovability, affect others and cast them into question, which blurs the very notion I'm discussing. I shouldn't have made the demarcation line seem so certain. Even saying that such a thing exists risks giving it more credence that it may deserve -- except as a matter of discussion.