Intelligence is probably the thing people spend the most time thinking about in this business, and I think it's one of the least important factors in long-run success. The returns to intelligence are just not that high in investing, and the reason is that markets are pretty efficient.
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The stock market is filled with individuals who know the price of everything, but the value of nothing. Prices are set at the margin by the most motivated seller and the most motivated buyer — and neither is representative of rational long-term value.
Philip Fisher — Common Stocks and Uncommon Profits
The market is brutally efficient at processing publicly available information. Your edge, if you have one, almost certainly lies in your ability to wait longer than the person on the other side of the trade — not in knowing something they don't.
Seth Klarman — Margin of Safety
It is not the neutrality of the judge that makes justice, but his passionate will to discover what is true. A judge who merely balances probabilities has abdicated his function.
Learned Hand — The Spirit of Liberty (address at 'I Am an American Day' ceremony, Central Park)