"Based on the authors' extensive teaching, and assuming no previous study in logic, this informal yet rigorous text covers the material of a standard undergraduate first course in mathematical logic. At each stage of the text new methods and concepts are introduced intuitively in terms of actual mathematical practice, and subsequently developed with clean formal mathematics. Practical examples are given for each idea as it is introduced, and extensive end of section exercises help consolidate the material. Solutions to many of the exercises are presented in an appendix."--BOOK JACKET.