Preface to the
Turing Centenary Edition
Alan Turing was born on June 23, 1912. The year 2012, the hundredth
anniversary of his birth, is providing the occasion for events and publica-
tions reflecting on and celebrating his achievements. I am delighted that
this updated version of my book will be part of the excitement, and I am
very grateful to Klaus Peters and Alice Peters for their help in making it
happen. For this edition, I’ve tidied up some loose ends and brought a few
things up to date, even commenting on IBM’s achievement in fielding their
Watson computer as a successful contestant on the popular television quiz
program Jeopardy.
The “universality” of the computers with which we interact today is
evident not only in the myriad of unrelated tasks ...