What's the problem with trump jokes?

[marble falls]

9. Tell your friend to google it ...

Exception that proves the rule

"The exception that proves the rule" is a saying whose meaning is contested. Henry Watson Fowler's Modern English Usage identifies five ways in which the phrase has been used, and each use makes some sort of reference to the role that a particular case or event takes in relation to a more general rule. Two original meanings of the phrase are usually cited. The first, preferred by Fowler, is that the presence of an exception applying to a specific case establishes that a general rule exists.

Wikipedia

https://www.phrases.org.uk/meanings/exception-that-proves-the-rule.html

https://proofed.com/writing-tips/exception-that-proves-the-rule/

https://grammarist.com/phrase/the-exception-that-proves-the-rule/

https://usdictionary.com/idioms/the-exception-proves-the-rule/