ABSTRACT
The object of this book is to explain ideas of probability that philosophers and others may need or want to understand. While this means introducing some elementary mathematics of probability, very little mathematical expertise is required to follow it, and the book contains no exercises to test or increase that expertise. In this respect it differs from some other introductions to probability written by or for philosophers, and also from most introductions to logic. In other respects, however, the book does provide material for introductory courses in probability analogous to those in logic. The former are indeed less common, partly because the need for them, although in my view no less, is less widely felt, and partly because there are, for this reason, few suitable textbooks for them. This I hope will become one of them.
