– I am not you. Is it not so?
– Yes, yes. You are not me and I am different from you.
– and I am a human.
– of course, you are a human.
– I am a human and you are different from me.
– Yes, I am different from you and you are a human.
– So you are not a human.
p.s. Based on a real story.
p.p.s. in the real story the second person was convinced about the conclusion. (450 BC)