A small leak can sink a great ship.
-Benjamin Franklin
That reminds me: when I was little, there was a puzzle in a happy meal that said, "Rearrange these letters to spell something that can make a canoe sink: ELAK." The correct answer, of course, was "leak". I was upset, because my answer was "a elk". (And now that I think about it, if you draw this as a causal diagram, "lake" should be a valid answer too.)
Every month on the month, Less Wrong has a thread where we post Deep Wisdom from the Masters. I saw that nobody did this yet for December for some reason, so I figured I could do it myself.
* Please post all quotes separately, so that they can be voted up/down separately. (If they are strongly related, reply to your own comments. If strongly ordered, then go ahead and post them together.)
* "Do not quote yourself." --Tiiba
* Do not quote comments/posts on LW/OB. That's like shooting fish in a barrel. :)
* No more than 5 quotes per person per monthly thread, please.