They would then be contradicting God, in which case, they would be wrong. It is not possible for finite men to reason their way to universals (not logically possible). One must start with universals and reason down to men.
Since this is a statement is a universal, reasoned to by you, a human, this must not be universal, therefore some finite men must be able to reason their way to universals, else what you said contradicts itself.
Hank