"proof"is i think somewhat elusive to define inasmuch as what would contain the acceptable constituents.however many looking at the evidence have arrived at faith including at least one lawyer examining the accounts of the ressurection-frank morrison-who moved the stone?
and quite a few scientists do recognize God as creator.
so i suspect that the definition of an agnostic is;- one that demands proof and rejects or ignores or mocks the evidence.