Back in 2008, Buffett said he was buying US stocks with his non-Berkshire money, with up to 100% of networth http://www.nytimes.com/2008/10/17/opinion/17buffett.html "So ... I’ve been buying American stocks. This is my personal account I’m talking about, in which I previously owned nothing but United States government bonds. (This description leaves aside my Berkshire Hathaway holdings, which are all committed to philanthropy.) If prices keep looking attractive, my non-Berkshire net worthwill soon be 100 percent in United States equities." If you are really rich, it makes all the sense in the world to have some money stashed away just in case there is some kind of black swan/tail event and you lose it all (or most of it). That's what I think he was doing by having some US bonds outside Berkshire. What is not consistent with that is to have evidence that the black swan is showing up (2008 crisis), then take the money that you had stashed away (that would guarantee you would be wealthy no matter what happened) then put it in something highly correlated to what your main assets are in. Essentially, Buffett shorted even more puts on the 'America always comes back' thesis , and he put even his safe cash in there. It gets worse when you consider that Berkishire is leveraged 1.2-1 or more. He is basically saying that the utility of money doesn't matter to him, risk of ruin doesn't matter to him, all that he cares about are benefits (better valuations/higher expected returns) But as Taleb shows here, you can add benefits all day long, when risk of ruin/downside risks are involved it doesn't matter how much you add benefits, its the negative side of the tail that matters This is also confimed by the Kelly formula that shows that you can keep adding benefits (bigger and bigger pay offs) but with uncertain win %'s (that is, with realistic win percentages), the recommended bet amount won't go up that much. At some level it just sorta stagnates. A 6-1 payoff bet with 50% win percetage leads to 41% bet, a 99-1 payoff with the same win pct leads to a 49% bet. Benefits don't change the math much Is Buffett just tail risk blind?