Ben Graham said to be a successful investors one needs first, reasonably good intelligence; second, sound principles of operation; and third, and most important, firmness of character. What did he mean by “firmness of character”? Operating in an intensely competitive domain with limited information and high stakes is psychologically demanding. We have to constantly work against our evolutionary instincts (conformity, attribution bias, loss aversion, narrative fallacy etc) while trying to generate sustainable returns in markets. Hence good investors are often contrarians, have high tolerance for uncertainty and are loners. Studies have shown that being a contrarian and standing against your social peer group activates anterior cingulated cortex and the insula in your brain which are also activated in case of real physical pain. As a contrarian investor you are buying what everybody else is selling and selling what everybody else is buying and this is to an extent biolo...