Warren Buffett says

“Investors should be skeptical of history-based models. Constructed by a nerdy-sounding priesthood using esoteric terms such as beta, gamma, sigma and the like, these models tend to look impressive. Too often, though, investors forget to examine the assumptions behind the models. Beware of geeks bearing formulas.”

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“We both insist on a lot of time being available almost every day to just sit and think. That is very uncommon in American business. We read and think. So Warren and I do more reading and thinking and less doing than most people in business.”

“Any business plan won’t survive its first encounter with reality. The reality will always be different. It will never be the plan.”

“It takes character to sit with all that cash and to do nothing. I didn't get top where I am by going after mediocre opportunities.”

“Warren talks about these discounted cash flows. I’ve never seen him do one.”