Introduction to Formal Logic

An Introduction to Formal Logic was first published by Cambridge University Press in November 2003. A heavily corrected reprint was published in April 2009. (You can tell them apart by looking at the publication details halfway down the verso of the title page — or by seeing whether the last paragraph of the Preface thanks people for corrections to the first printing.)

The headline news is that this is an initially very gentle-paced introduction to logic by trees, though it does get as far as a completeness proof for quantificational logic. It is the text book for the compulsory first-year logic course for Cambridge philosophers. Click on the thumbnail of its cover to go to the publisher’s page for the book. And from there you can do a Google Book Search which will give you a very good idea of what is in the book, the topics it covers and its approach.

There are additional support materials available:

There are not only the inevitable typos but also a few quite horrible “thinkos” in the first printing. So, if you are using that version of the book, please

But while that gives a fairly complete list of the typos in the first printing, it does not explain all the little improvements in the second printing. So ignore second-hand copies of the first version: buy (or get your library to buy) the significantly improved, and still pretty cheap, later version!