Ah yes, I remember when I was told something like that. It was my topology lecturer. Then he said that as a corollary of this any continuous function that maps an even-dimensional sphere into itself has either a fixed point or a point that maps onto its own antipodal point. You can however comb a hairy doughnut.Jedamethis said:"You can't comb a hairy ball."
I didn't believe it at first. So I thought about it for a while, tried a few ways. You can't.
I learned something that day.
Sometimes, the only way to find out if something is impossible is to try it.
I was told that no matter how bad something is, there's always something you can learn from it. It's especially good in job hunting, no matter how bad an aptitude test or interview goes.