"For having lived long, I have experienced many instances of being obliged, by better information or fuller consideration, to change opinions, even on important subjects, which I once thought right but found to be otherwise.
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Selected Quotes of Yakov Borisovich Zel'dovich 1914-1987
"If Landau would have been here he would have stopped you after twenty seconds
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"Frequently in error, never in doubt (said of cosmologists...)
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