"I think Stefan does not realize that logic is not the same as input and output of the logic. And whatever is the logic, we can manipulate the output by manipulating input."For goodness sakes, he realises this; he's not an imbecile.The problem was you were going on about his alleged blind spot (and, in other areas, I'll acknowledge I think he has a couple) while asking him ridiculous questions like has he heard of a black hole (who hasn't) and not making any good arguments for your position.It's one thing to say someone has a blind spot, but you actually then have to show that. Even if they can't see it, the audience might. You spectacularly failed at that and I'm about as truth-seeking person as you will ever find.