Re: More complex numbers than reals?

Am 11.07.2024 um 02:16 schrieb Chris M. Thomasson:
 

{a, b, c} vs { 3, 4, 5 }
>
Both have the same number of elements, [...]

 HOW do you know that? Please define (for any sets A, B):
      A and B /have the same number of elements/ iff ___________________ .
 (i.e. fill out the blanks). :-)
 Hint: That's what Ben Bacarisse is asking for.
 Sure, it's "obvious" for us. But how would you define "have the same number of elements" (in mathematical terms) such that it can be DEDUCED (!) für certain sets A and B?
 ________________________________________
 Ok, I'm slighty vicious now... :-)
 If a = b = c, {a, b, c} still has "the same number of elements" as {3, 4, 5 }? :-P