A list of truly impossible things?

Hello, Does anyone have a list of truly impossible things? Or events / circumstances? My teacher says the whole 'nothing is impossible' cliche, which I know to be false. Anyways, does anyone know impossible things? Like so impossible, it's even paradoxal? Like standing in an empty room (once you... show more Hello,

Does anyone have a list of truly impossible things? Or events / circumstances? My teacher says the whole 'nothing is impossible' cliche, which I know to be false.

Anyways, does anyone know impossible things? Like so impossible, it's even paradoxal? Like standing in an empty room (once you stand in it, the room is no longer empty). 10 points to the best one. Thanks!
7 answers 7