It is also well-known that horses have forelegs in front and two legs in back. However, suppose that there is a horse somewhere that does not have an infinite number of legs. Pie are round. Cornbread are square. Statisticians probably do it.
Algebraists do it in groups.
C programmers do it with long pointers. No cat has eight tails. A cat has one tail more than no cat. Therefore, a cat has nine tails. Just give us serviceable mathematics.