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amavectyesterday at 4:08 PM1 replyview on HN

No surjective function exists from names to real numbers (diagonalization). With any naming scheme, some unnamed real numbers always remain.

On the other hand, given any real number, I can name it. I'll run out of unique names, since no injective function exists from real numbers to names.

So, some unnamed real numbers will always remain (non-constructively), I can make real numbers that escape a naming scheme (constructively), and no unnameable real numbers exist.


Replies

ithkuilyesterday at 11:27 PM

What does "naming" mean?

Assigning a symbol? But who said that the set of symbols must be countable?

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