"The book is rather snappily written. It's informal, breezy - sometimes positively jaunty - and always directed to the reader. It can't be emphasized enough that the great thing about this book is its many well-chosen, completely solved exercises. This alone makes it a valuable text, especially for self-study."
Robert J. Irwin, Hamilton College for SIGACT News
Two of the fundamental notions of mathematics, proof and calculation, are intimately related. Proofs can involve calculations, and the algorithm underlying a calculation should be proved correct. The aim of the author is to explore this relationship. The book itself forms an introduction to simple type theory. Each of its 52 sections ends with a set of exercises, some 200 in total. These are designed to help the reader get to grips with the subject, and develop a further understanding. An appendix contains complete solutions of these exercises.