For centuries, mathematicians have categorized infinities into a kind of ladder. The infinite set of natural numbers (1, 2, 3, and so on) sits on one rung. On a higher rung, the infinite set of real ...

One question has preoccupied humankind for thousands of years: Do infinities exist? More than 2,300 years ago Aristotle distinguished between two types of infinity: potential and actual. The former ...