„An expert is a person who has found out by his own painful experience all the mistakes that one can make in a very narrow field.“
As quoted by Edward Teller, in Dr. Edward Teller's Magnificent Obsession by Robert Coughlan, in LIFE magazine (6 September 1954), p. 62 http://books.google.de/books?id=I1QEAAAAMBAJ&pg=PA62
As quoted by Edward Teller (10 October 1972), and A Dictionary of Scientific Quotations (1991) by Alan L. Mackay, p. 35
Variante: An expert is a man who has made all the mistakes which can be made in a very narrow field.
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