The nature of our language tends to force us into “yes/no”; something is or is not, you either have a proof or you do not. But once we admit there is a changing standard of rigor, we have to accept that some proofs are more convincing than other proofs. If you view proofs on a scale much like probability, running from 0 to 1, then all proofs lie in the range and very likely never reach the upper limit of 1, certainty.
