This elementary introduction to philosophical problems and issues in mathematical thought, speech, teaching, and learning is now available in a revised and expanded second edition. It is designed for teachers and students of mathematics and philosophy alike. Real numbers form the basis for discussion and remain a continuous touchstone throughout the work, which incisively addresses a range of mathematical and philosophical problems and questions. The work provides an overview and engages in an in-depth discussion of viewpoints held throughout the history of mathematics and philosophy up to the present day.