“The object of mathematics is to discover "true" theorems. We shall use the term "valid" to describe statements formed according to certain rules and then shall discuss how this notion compares with the intuitive idea of "true."”
             Set theory and the continuum hypothesis, p. 8. https://books.google.com/books?id=Z4NCAwAAQBAJ&pg=PA8 
Set Theory and the Continuum Hypothesis (1966)
        
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Paul Cohen 5
American mathematician 1934–2007Related quotes
Great Books: The Foundation of a Liberal Education (1954)
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                                        Lotfi Asker Zadeh, George Jiri Klir, Bo Yuan (1996) Fuzzy Sets, Fuzzy Logic, and Fuzzy Systems: Selected Papers. p. 238 
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