What do you want to avoid? Such an easy answer: sloth and unreliability. If you're unreliable it doesn't matter what your virtues are. You're going to crater immediately. Doing what you have faithfully engaged to do should be an automatic part of your conduct. You want to avoid sloth and unreliability.

If you have competence, you pretty much know its boundaries already. To ask the question (of whether you are past the boundary) is to answer it.

Even in pure mathematics they can't remove all paradox, and the rest of us should also recognize we are going to have to endure a lot of paradox, like it or not.

We don't have any miraculous way of avoiding taxes at Wesco and Berkshire.

I try to get rid of people who always confidently answer questions about which they don't have any real knowledge.

You must know the big ideas in the big disciplines, and use them routinely - all of them, not just a few. Most people are trained in one model - economics, for example - and try to solve all problems in one way. You know the old saying: to the man with a hammer, the world looks like a nail. This is a dumb way of handling problems.

I also want to raise the possibility that there are, in the very long term, "virtue effects" in economics- for instance that widespread corrupt accounting will eventually create bad long term consequences as a sort of obverse effect from the virtue-based boost double-entry book-keeping gave to the heyday of Venice. I suggest that when the financial scene starts reminding you of Sodomand Gomorrah, you should fear practical consequences even if you like to participate in what is going on.