"The possibility that stock value in aggregate can become irrationally high is contrary to the hard-form "efficient market" theory that many of you once learned as gospel from your mistaken professors of yore. Your mistaken professors were too much influenced by "rational man" models of human behavior from economics and too little by "foolish man" models from psychology and real-world experience."

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'Crowd folly', the tendency of humans, under some circumstances, to resemble lemmings, explains much foolish thinking of brilliant men and much foolish behavior - like investment management practices of many foundations represented here today. It is sad that today each institutional investor apparently fears most of all that its investment practices will be different from practices of the rest of the crowd.

— Charlie Munger