John Laird (1887-1946) was a Scottish philosopher who specialised in metaphysics and moral philosophy. In this early work, which was originally published in 1920, Laird set out to analyse some of the more perplexing problems of philosophical realism. The text includes a brief survey of philosophical realism at the beginning and critical notes throughout. This book will be of value to anyone with an interest in the works of Laird and the history of philosophy.