The pervasiveness of Protestant natural law in the early modern period and its significance in the Scottish Enlightenment have long been recognized. This book reveals that Thomas Reid (1710–1796)—the great contemporary of David Hume and Adam Smith—also worked in this tradition. When Reid succeeded Adam Smith as professor of moral philosophy in Glasgow in 1764, he taught a course covering pneumatology, practical ethics, and politics. This section on practical ethics took its starting point from the system of natural law and rights published by Francis Hutcheson. Knud Haakonssen has reconstructed it here for the first time from Reid’s manuscript lectures and papers, and it provides a considerable addition to our understanding not only of Reid but also of the thought of the Scottish Enlightenment and of the education system of the time. The present work is a revised version of a work first published by Princeton University Press in 1990, which has long been out of print.