If you don't accept adding and subtracting numbers as allowed mathematical transactions, multiplication doesn't make sense at all. It isn't arbitrary. It's fundamental basic accounting.
What you just said is at best irrelevant and at worst meaningless. No, the fact that multiplication is defined in terms of addition does not mean that it is required or natural to evaluate multiplication before addition when parsing a mathematical expression. The latter is a purely syntactic convention. It is arbitrary. It isn't "accounting."
If you don't accept adding and subtracting numbers as allowed mathematical transactions, multiplication doesn't make sense at all. It isn't arbitrary. It's fundamental basic accounting.
What you just said is at best irrelevant and at worst meaningless. No, the fact that multiplication is defined in terms of addition does not mean that it is required or natural to evaluate multiplication before addition when parsing a mathematical expression. The latter is a purely syntactic convention. It is arbitrary. It isn't "accounting."