Robert Morris has a very unusual quality: he's never wrong. It might seem this would require you to be omniscient, but actually it's surprisingly easy. Don't say anything unless you're fairly sure of it. If you're not omniscient, you just don't end up saying much. More precisely, the trick is to pay careful attention to how you qualify what you say. ... He has an almost superhuman integrity. He's not just generally correct, but also correct about how correct he is.

--Paul Graham