\Me*men"to mo"ri\ [L.] Lit., remember to die, i.e., that you must die; a warning to be prepared for death; an object, as a death's-head or a personal ornament, usually emblematic, used as a reminder of death.
Source: Webster's Revised Unabridged Dictionary, © 1996, 1998 MICRA, Inc.
I read somewhere once that this was spoken to a Caesar once, but I could be wrong*.
But it's good advice. Remember thou art mortal, think about the future (to quote the Joker). But it's also important to remember that we all do stupid things. All of us. Well, ok, one man I can think of never did. But other than Him, even the most brilliant thinkers had their moments of sheer idiocy. I guarantee it.
I'd like to think I'm a fairly intelligent individual, but I am aware of my own failings. And that is why I named my blog Memento Moron: because I like silly puns, and because I think it's important for all of us to remind ourselves of what I said two paragraphs ago: I could be wrong.
Except about this.
My good friend 51st State from over at the Rottie shows me that not only could I be wrong, I probably was. He writes:
If I recall, it wasn't said to the Caesars, but to the succesful returning generals as they were paraded through Rome to meet with Caesar. A Caesar was more or less deified, but the crowds cheered for the generals, feeding their pride. Thus, someone would remind them, "Remember, thou art mortal" contrasting them against the Caesar, humbling them. Could be wrong, but that's what I remember...
That makes a lot of sense. I knew it was from Roman times (The fact that it was Latin being my first clue -- duh), even if my details were off. Which just goes to show.