Deductive Reasoning in First-order Logic 179 The Lady or the Tiger? (1982), Alice in Puzzle-Land (1982), To Mock a Mockingbird (1985), Forever Undecided (1987), Satan, Cantor, and Infinity (1992), The Riddle of Scheherazade (1997), King Arthur in Search of his Dog (2010), The Gödelian Puzzle Book: Puzzles, Paradoxes and Proofs (2013), and many others As well as teaching and writing about logic, Smullyan is an accomplished piano player and has produced many recordings of his favorite classical piano pieces In 2004 the filmmaker Tao Ruspoli produced a documentary film about him called This Film Needs No Title: A Portrait of Raymond Smullyan Melvin Fitting (born 24.1.1942) is an American logician, mathematician, philosopher, and computer scientist with very broad interests, and has made many contributions to mathematical, philosophical, and computational logic Fitting obtained his doctorate in mathematics from Yeshiva University, New York under the supervision of Raymond Smullyan From 1968 to 2013 he was a professor at City University of New York, Lehman College and at the Graduate Center, in the departments of Computer Science, Philosophy, and Mathematics He is currently an Emeritus Professor there Fitting’s philosophy of logic can be formulated succinctly as follows (quoting Wikipedia): “There are many logics Our principles of reasoning vary with context and subject matter Multiplicity is one of the glories of modern formal logic The common thread tying logics together is a concern for what can be said (syntax), what that means (semantics), and relationships between the two A philosophical position that can be embodied in a formal logic has been shown to be coherent, not correct Logic is a tool, not a master, but it is an enjoyable tool to use.” Fitting has worked in numerous diverse fields of logic, an impressive testimony of which is the long list of well-known books he has written over the years including Intuitionistic Logic, Model Theory, and Forcing (1969), Fundamentals of Generalized Recursion Theory (1981), Proof Methods for Modal and Intuitionistic Logics (1983), First-Order Logic and Automated Theorem Proving (1990), Set Theory and the Continuum Problem, with Raymond Smullyan (1996), First-Order Modal Logic, with Richard Mendelsohn (1998) Types, Tableaus, and Gödel’s God (2002), and Incompleteness in the Land of Sets (2007) In addition, he has carried out important work on tableaux methods of proof for modal logics, bilattices and the theory of truth, many-valued modal logics, and justification logic