Logical Forms: An Introduction to Philosophical Logic

The first time I read this book I found it seriously hard work, but coming back to it a year later, and a year further into my philosophy degree I found it helpful and reasonably clear. Perhaps there is no easy way into philosophy of logic, and this book reflects that.At times I felt the text could be shorter, but overall it is good. I also found the constant cross referencing to other parts of the book a little irritating, but not sure there is an easy alternative.The strength of the book is its explanation of key logical concepts - validty, truth, propositional logic, modal logic, and quantification - all set within in a framework of long exposition of the challenges of formalisation. A good book for an undergraduate philosophical logic course. As a comparison, it is more interesting, but harder work and less easy to follow, than Guttenplan's "The languages of logic".