Then for the first time it dawned on him that classing all drowthers together made no more sense than having a word for all animals that can’t stand upright on two legs for more than a minute, or all animals with dry noses. What possible use could there be for such classifications? The word “drowther” didn’t say anything about people except that they were not born in a Westil Family. “Drowther” meant “not us,” and anything you said about drowthers beyond that was likely to be completely meaningless. They were not a “class” at all. They were just… people.
Orson Scott Card, The Lost Gate
As my math teacher always said,
Why is it repulsive...? I guess I don’t get it. I mean sure, it’s not a subspace… is that what they mean?
It’s extremely inelegant, and finding yourself using one means you’re running into a dead end.
I don’t see why a complement would be inelegant. It’s just one extra bit of specification.
Now, non-definable non-computable numbers (or sets), they are inelegant :-)