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was an American mathematician, logician, philosopher, [https://en.wikipedia.org/wiki/Magician magician], [https://en.wikipedia.org/wiki/Pianist pianist], and Professor Emeritus professor of Philosophy from at [https://en.wikipedia.org/wiki/Indiana_University_Bloomington Indiana University Bloomington]. He held a Ph.D. in mathematics on the theory of [https://en.wikipedia.org/wiki/Formal_system formal systems] from [https://en.wikipedia.org/wiki/Princeton_University Princeton University] under advisor [[Mathematician#Church|Alonzo Church]] <ref>[http://genealogy.math.ndsu.nodak.edu/id.php?id=8027 The Mathematics Genealogy Project - Raymond Smullyan]</ref>. Smullyan was author of fourteen books and of numerous research articles on the topics of [https://en.wikipedia.org/wiki/Mathematical_logic mathematical logic], [https://en.wikipedia.org/wiki/First-order_logic first-order logic], [https://en.wikipedia.org/wiki/Set_theory set theory], theory of [https://en.wikipedia.org/wiki/Computable_function computable functions], [https://en.wikipedia.org/wiki/Recreational_mathematics recreational mathematics], [https://en.wikipedia.org/wiki/Mathematical_game mathematical games] and [https://en.wikipedia.org/wiki/Mathematical_puzzle puzzles], [[Retrograde Analysis|retrograde chess problems]], and [https://en.wikipedia.org/wiki/Eastern_philosophy Eastern philosophy]. He has been a contributor to [[Scientific American]] <ref>[http://www.indiana.edu/~phil/people/smullyan.shtml Raymond Smullyan | Department of Philosophy] | [https://en.wikipedia.org/wiki/Indiana_University_Bloomington Indiana University Bloomington]</ref>.