His early papers are paralyzingly beautiful but they are thoroughly corrupt with errors, and this has delayed the publication of his collected works for almost ten years. A man whose errors can take that long to correct is quite a man.

Memorial lecture delivered on 13 December 1965 at UNESCO headquarters to commemorate the tenth anniversary of Albert Einstein's death, as quoted in Silvan S. Schweber, Einstein and Oppenheimer: The Meaning of Genius (Cambridge: Harvard University Press, 2008), pp. 279-280.