M: An argument isn’t just contradiction.
A: It can be.
M: No it can’t. An argument is a connected series of statements intended to establish a proposition.
A: No it isn’t.
M: Yes it is! It’s not just contradiction.
A: Look, if I argue with you, I must take up a contrary position.
M: Yes, but that’s not just saying ‘No it isn’t.’
A: Yes it is!
M: No it isn’t! —The Argument Sketch [Monty Python]