[atwood22]

No, the mathematical definition of counting (i.e. whether or not a set is countable) involves mapping to the natural numbers, which doesn’t include 0.

[kazinator]

I don't think your definition is complete. We can count a set by mapping its elements to the natural numbers, and then identifying that number which is highest. However, we must have a provision for identifying zero as the highest when the set and mapping are empty.

[8note]

Math counting doesn't care where you start. You could start -400 if it's useful for the problem

[lupire]

You can name things however you want, but there is a canonical bijection to zero-based ordinals.

https://en.m.wikipedia.org/wiki/Ordinal_number