MAA Distinguished Lecture : The Saga of the Hardest Logic Puzzle Ever
Abstract. The hardest logic puzzle ever was introduced by philosopher George Boolos in 1996. We are to imagine three gods: one who always makes true statements, one who only makes false statements, and one who randomly answers true or false at his whim. The gods will answer any yes/no question that is put to them, but they will answer in their own language, in which the words for yes and no are da and ja, in some order. Sadly, you do not now which word means what. Your task is to determine who is who in just three questions. The puzzle has spawned a veritable industry of journal articles, in which authors present ever more ingenious solutions, and ever more fiendishly difficult variations. We will discuss the various approaches to this puzzle and its variations. Along the way we will consider aspects of the history of logic, focusing especially on puzzle masters like Lewis Carroll and Raymond Smullyan.
Speaker Bio. Jason Rosenhouse received his PhD in mathematics from Dartmouth College in 2000, specializing in algebraic graph theory. Currently he is a professor of mathematics at James Madison University, in Harrisonburg, Virginia. He is the author or editor of seven books including The Monty Hall Problem: The Remarkable Story of Math’s Most Contentious Brainteaser, and Among the Creationists: Dispatches from the Anti-Evolutionary Front Line, both published by Oxford University Press. With Laura Taalman he is the author of Taking Sudoku Seriously: The Math Behind the World’s Most Popular Pencil Puzzle, which received the 2012 PROSE award from the Association of American Publishers for the best popular math or science book of the year. When not doing math he enjoys playing chess, cooking, and reading locked-room mysteries.