2013 Reprint of 1941 Revised and Enlarged Edition. Exact facsimile of the original edition, not reproduced with Optical Recognition Software. Tarski is considered one of the five greatest logicians of all time, alongside Aristotle (384-322 BCE), Boole (1815-1864), Frege (1848-1925) and Godel. This book, together with Aristotle's "Prior Analytics" and Boole's "Laws of Thought," should form the core of any logic library. This classic undergraduate treatment examines the deductive method in its first part and explores applications of logic and methodology in constructing mathematical theories in its second part. A thought-provoking introduction to the fundamentals and the perfect adjunct to courses in logic and the foundations of mathematics. Exercises appear throughout.