Originally published in 1905, this book contains the first two books of the Latin text of Cicero's Disputations at Tusculum, the first volume of Dougan's two-volume critical edition of the text. The Latin is accompanied by a running commentary, and Dougan provides a detailed introduction on the place of the Disputations in Cicero's philosophical canon, as well as on the arguments contained in the book and the manuscript sources for the text. This book will be of value to anyone with an interest in the works of Cicero.