Preface About three years ago, while in Washington, D.C. for a meeting, I came across a bookstore specializing in used books on logic and literature. Inside, I came across a thin volume by Martin Gardner called Logic, Machines, and Diagrams . Opening that book brought about a small epiphany. But these thoughts were only the backdrop against which my psychodrama played itself out. To explain, I must go back several more years.
Logic is the science of reasoning.
In this regard it is at the very heart of all rational inquiry, transcending any particular branch of engineering, science, or mathematics. I became interested in logic in high school in the late 1950's and have happily spent my professional life in its pursuit. In the early 1980's, when I was on the faculty at Stanford University, the first Macintosh computers came on the market with a whopping 128K of memory. A friend and colleague, John Etchemendy, and I were inspired by the visual power of the Macintosh to try to develop programs for it that would help our students visualize and understand some of the more abstract notions of logic. This collaboration has over the past decade led to the development of Turing's World , Tarski's World , and most recently, Hyperproof .