The natural numbers (1, 2, 3, etc.) are of course "infinite" - however, they are also "countable". (For any natural number you pick, if you count long enough, y

The natural numbers (1, 2, 3, etc.) are of course "infinite" - however, they are also "countable". (For any natural number you pick, if you count long enough, you'll eventually get to it.) That doesn't mean you'll ever have counted /all/ the natural numbers, but you can count to any arbitrary one. For contrast, the real numbers, although also infinite, are "uncountable" - any way you start counting, there are real numbers that you will /never/ reach.