There is a translation problem here that I suspect started with Latin. What the saying really means is "the (apparent) exception that tests the rule". So if there is a case that (apparently) proves the rule wrong, but it can be shown that rule does not apply to that case, then the case is actually evidence for the rule instead of against it.TheDarkEricDraven said:"The exception that proves the rule". What the fuck does that mean? If its an exception, it doesn't prove anything!
I think it is a translation problem, because in Spanish probar means "to test" or "to try", but is also used to mean "to prove". And as spelled it looks more like "prove" than "test". In English there are two words with slightly different meanings, but in at least one language based on Latin, there is one word that combines those two meanings. Easy to understand the fuck-up.