Translated by Francis H. Cook, this volume comprises three important texts of the Yogacara school. ""Demonstration of Consciousness Only"" is an in-depth commentary on Vasubandhu's ""Thirty Verses on Consciousness Only"" by Hsuan-tsang. It also includes the text of Vasubandhu's ""Thirty Verses"" and ""The Treatise in Twenty Verses on Consciousness Only"", which presents a logical defense of Yogacara doctrine.