Jumping to conclusions. We all create hypotheses in undisciplined fashion, and then you have to go back and be intellectually disciplined.

Impatience. My mind moves rapidly.

I probably want to be liked too much. This is one difference between me and Steve Levitt . Steve Levitt is also much smarter than me and much more successful than me. And that doesn’t bother me at all, but he said he also doesn’t care what anyone thinks about him, or doesn’t seem to care what anyone thinks about him. I actually do care what people think about me. I’d quite like people to think I’m a nice guy, so I’m probably self-censoring at times. Say, maybe I won’t say that because people wouldn’t like that. And that’s probably a fault in a newspaper columnist — you probably shouldn’t care what people think about you, but that’s the way it is.

Ironically, though, this is also the purchase in which I made my biggest mistake - of a kind, however, never recognized on financial statements. We paid $600 million in 1989 for Gillette preferred shares that were convertible into 48 million (split-adjusted) common shares. Taking an alternative route with the $600 million, I probably could have purchased 60 million shares of common from the company. The market on the common was then about $10.50, and given that this would have been a huge private placement carrying important restrictions, I probably could have bought the stock at a discount of at least 5%. I can't be sure about this, but it's likely that Gillette's management would have been just as happy to have Berkshire opt for common. But I was far too clever to do that.

I believe that I had something called epigenetic imprinting, which I actually read about in a book called The Female Brain by Louann Brizendine. Not to self-promote too much, but I loved it so much I wrote a movie with a brilliant comedian named Neil Brennan and made the move this year. That’s how profoundly it changed my life, because I believe that the more we know about our neural brain wiring, the more freedom we have and the more patience we have with ourselves.

I think stress ages us the most, and stressing about food is the worst. I eat a high-fat diet because it gives me the most energy and makes me think about food less. I can't be obsessing about food all day if I'm hungry because I only ate a salad. I also like feeling full. I will eat a donut if it makes me have a happy day. And for me, eating things that are considered 'bad' is part of what really gets me motivated to work out [laughs]. At this point in my life, I'll take what I can get.