I view catchphrases as a way to shortcut thought, consideration and communication. Know what I mean? In a culture that idolizes stupidity (Jackass) and disparages intelligence (Jeopardy), speaking in meaningless, fill in the blank, phrases is how to fit in. The listener can project his/her/hir own meaning to what you say and everything is groovy. Kopasetic. Eukanuba. That's cool. (But not hot.) I am more interested in how a phrase evolves over time. For example, the phrase, "There is no honor among thieves." Something that seemed obvious enough. But it became, "You know what they say about honor among thieves." Then it became, "Honor among thieves." And now many people using that phrase think thieves have some kind of honor, when the fact is, they don't. We aren't supposed to think too much about what we say. After all, he who hesitates is lost. Look before you leap. You can't judge a book by it's cover. Clothes make the man. No good deed goes unpunished. But what about connotation? Is "Way Out!" better than "Far Out"? Is "Right On!" more emphatic than "Word!"? Rap used to mean straight talk, does that make John McCain a rapper? And who will be considered the superior wordmeister, Eric Severeid or Steven Colbert? The answer, "my friend" ( as John McCain and every English speaker from the Middle East says ) is blowing in the wind. All sound and fury signifying...(you fill in the blank)? Filling in that blank is the meaning of life... Man.

Hey there, I think you misunderstood "honor among thieves". I'm pretty sure that's how it started, and there was never a version that went "no honor among thieves," unless the latter was itself a misquoting. When someone says there is honor among thieves, it's meant to say that within a group of unlawful/unscrupulous/unsavory people there is respect for one another (just not for their victims).

I just thought of an example that does demonstrate what you were saying about honor among thieves though: the exception that proves the rule (admittedly not a catch phrase). People still use this a lot but if you think it through logically it makes no sense - how can an exception prove anything except its opposite? But I read that the phrase originated at time when the meaning in English of "prove" was not "demonstrate to be true" but rather "test, try" - closer to its Latin cognate. If you read the phrase as "the exception that tests the rule" it suddenly makes a lot more sense. For any given rule, the examples that demonstrate it are much more numerous than those that contradict it, so pointing out the exceptions makes the rule stand out more clearly.

I don't know, "the exception that proves the rule" always made sense to me, even with the current definition of "proves". I've always thought of it as pointing out that if an exception is rare enough to stand out, it demonstrates that the rule is valid, even if not 100% true all the time. If the exception were common enough to not stand out, the rule wouldn't be valid often enough to be stand as a rule.

If that makes any sense ;-). OTOH, that's what's so elegant about that phrase, it expresses a complex hard to describe idea, succinctly and clearly. Which, as another person has already stated, is one factor that makes a good catchphrase valuable.