I would have private conversations with [Buckminster Fuller]. I once had an argument, for four hours, about the existence of the Mobius strip. Because he believed in the Klein Bottle, you see. And I said, "How in hell can you claim to believe in the Klein Bottle and think that the Mobius strip is dubious?" He said, "Well, it's a torus." I don't know what he had in his mind as a mathematical background, because I don't think he got topology. Because, in other words, the Mobius strip didn't have angles in it.