"Discovered" makes more sense to me than "invented." Like, if we hadn't come along and starting counting on our fingers and toes, there would be no maths? Meh. There might not be maths textbooks, but there would still be maths.

An epiphany doesn't imply an invention. By definition, an epiphany means you just realised (discovered) something.

Somewhere out there are a bunch of equations that no-one has discovered yet, but which are invariably true. Even something like 13478342470 + 234890584325 might never have been calculated, but I would hardly say if I solved it, that would make me an "inventor" of maths.

p.s. The exception to the rule would be Ong, who does invent his own maths.