This volume commemorates the work of Alan Turing, who not only introduced the most persuasive and influential concept of a machine model of effective computability but also anticipated in his work contemporary debates about the extent and limitations of mechanistic explanations of nature. Turing's paper "On Computable Numbers, With an Application to the Entscheidungsproblem" appeared in 1937. It contained Turing's thesis that every "effective" computation...