An Introduction to Formal Logic was first published by Cambridge University Press in November 2003.
However, a heavily corrected reprinting was came out in April 2009 (that version was reprinted again in late 2010, and again in 2011). You should be using this much improved printing. You can tell the versions 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. (NB: A corrected reprint doesn’t count as a new edition so it doesn’t have a new ISBN: but the revised version will be what is supplied by bookshops, Amazon, etc.)
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 (included for enthusiasts). 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 look at the table of contents and a short excerpt.
There are additional support materials available:
- Crucially, the answers to nearly all the end-of-chapter exercises in the book.
- The Worksheets for the Cambridge 1A course.
- Some lecture overheads, additional draft chapters and various handouts.
There are not only the inevitable typos but also a few quite horrible “thinkos” in the first printing. So, if you are still using that version of the book, please
That gives a fairly complete list of the outright typos in the first printing (though on p. 4, B should read “Everyone admires some logician; whoever admires someone respects them. So everyone respects some logician”). But note, the list does not catalogue all the little improvements in the second printing where the text has been improved. So please just ignore second-hand copies of the first version: buy (or get your library to buy) the significantly improved, and still pretty cheap, later version!