Why does 1 + 1 = 2?

Here's the deal. a + 0 = a, and that means a + s(b) = s(a-b)

So 1 + 1 = a + s(o) = s(0+1), thus s(1) = 2

So one plus one equals two.

The arguments against that are philosophical sleight-of-hand that requires word games and altering the nature and intent of the question being asked, not a reflection of reality.

She puts a hand to her forehead

None of the people seriously pushing that argument really understand even the basics. The state of math proficiency is abysmal!