This book provides a detailed exposition of one of the most practical and popular methods of proving theorems in logic, called Natural Deduction. It is presente

Here is an extensive treatment of Natural Deduction and related proof systems, focused on practical aspects of proof methods. Necessary background material is p

"Necessity is the mother of invention. " Part I: What is in this book - details. There are several different types of formal proof procedures that logicians hav

This 2006 book provides an accessible, yet technically sound treatment of modal logic and its philosophical applications.

This long-awaited book replaces Hughes and Cresswell's two classic studies of modal logic: An Introduction to Modal Logic and A Companion to Modal Logic. A New