Over the long history of Buddhism, many schools of thought developed. Precisely when one school or another appeared is usually controversial. So it should come as no surprise that establishing the date of the foundation of the Yogacara school is controversial. It is believed that the school was founded by two brothers, Asanga and Vasubandhu. According to Louis de La Vallee Poussin, the brothers lived during the early 4th century. Other scholars place them in the latter half of the 5th century. In either case, their school of thought is among the last to develop in India.
Vasubandhu is deemed responsible for two treatises that present the central ideas of the Yogacara school: the Viṃśatikā-vijñaptimātratāsiddhi and the Triṃśikā-vijñaptimātratāsiddhi. These Sanskrit texts are now lost to us, but both were translated into Chinese numerous times. From these translations we now have English versions: The Treatise in Twenty Stanzas on Representation-Only and The Treatise in Thirty Stanzas on Representation-Only respectively. The edition of the Viṃśatikā reviewed here contains both the Chinese translation by Hsuan Tsang and the English version by Clarance Hamilton.
The Treatise in Twenty Stanzas defends Yogacara doctrines primarily by addressing critiques advanced by other Buddhist schools, thus clearing the way for the acceptance of the Yogacara doctrines. It is in The Treatise in Thirty Stanzas that Vasubandhu presents a fuller, positive treatment of his thinking. The central doctrine which Vasubandhu seeks to make tenable is that all that exists is, according to Hamilton's translation, is "representation." Others translate "representation" as "thought," "mind," "consciousness," or "discernment." The Yogacara view has often been described as a form of idealism.
Most broadly speaking, Vasubandhu frames his arguments by considering the relationship between objects of representation, representations, and the ego to which objects are represented. Of these, only representations are real. Vasubandhu argues against the Sarvastivadin view that both objects and representations are real, against the Madyamikan view that both objects and representations are equally unreal, and against the Sautrantikan view that representations are merely modes of mental functioning.
The main target of his arguments are the objections of realists, i.e., those who posit an objective world, independent of thought. As nearly all Buddhists deny the existence of the self, a refutation of the ego to which objects are represented isn't necessary. To refute the objections of the realist's, Vasubandhu attempts to show that his idealism can explain adequately that (1) sense objects (representations) can be fixed in space and time, (2) they can be shared in a publicly among numerous steams of consciousness, and (3) they can have a practical function.
In a more positive attack on realism, Vasubandhu argues that the elements that might make up an objective world are insubstantial. Of course this view could be extended to the representations that Vasubandhu asserts are real. His defense against the insubstantiality of objects and representations relies upon the distinction between ordinary cognition and the cognition of an enlightened being. Ordinary cognizers might easily reject the substantiality of representations and adopt a kind of nihilism; however, a fully enlightened cognizer will recognize a supramundane realm of elements. By availing himself of this supramundane reality that is intuited only by the enlightened, Vasubandhu comes down squarely in the camp of mysticism. This is not meant as a refutation of his views, but merely that the methods of ordinary perception and reason are not sufficient to reveal absolute truth. To discover this, one must adopt the yogic practice that leads to transcendent knowledge; hence, his school of thought is called "Yogacara."