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Mathematics

The True Nature of Infinity: Countable vs Uncountable

Quick fact

Georg Cantor showed that the infinity of real numbers is strictly larger than the infinity of natural numbers, even though both are infinite. In fact, there are infinitely many sizes of infinity, and the size of the real numbers is just the second-smallest one.

Why this is interesting

You've probably been told that infinity is not a number, but what if I told you that some infinities are actually bigger than others? In fact, there are infinitely many different sizes of infinity.