The 2-volume introductory textbook on logical number theory - or, number theory as studied by the logician - consists of this first volume that can stand on its own as a somewhat unorthodox introduction to mathematical logic for undergraduates, and a second volume to follow soon with more sophisticated content and treatment but still accessible to students having read volume I or had a standard introductory course. The author is well known beyond his own field of specialisation for his expository talent and his lucid and enjoyable writing style.