Nor did true Buddhism at first concern itself with any form of philosophical or metaphysical teaching, which it did not consider helpful for the attainment of the only kind of true knowledge worth striving for—the knowledge of the origin of suffering and its remedy—the knowledge that suffering and pain arise from indulging lusts, and that life is inseparable from suffering, and is an evil to be got rid of by suppressing self and extinguishing desires. In the Mahā-parinibbāna-sutta (Rhys Davids, II. 32) is recorded one of the Buddha’s remarks shortly before his decease:— ‘What, O Ānanda, does the Order desire of me? I have taught the law (desito dhammo) without making any distinction between esoteric and exoteric doctrine (anantaram abahiram karitvā). In the matter of the law, the Tathāgata (i.e. the Buddha) has never had the closed fist of a teacher (āćariya-muṭṭhi)—of a teacher who withholds some doctrines and communicates others.’ In short, he was opposed to mysticism. Nevertheless, admitting, as we must, that early Buddhism had no mysteries reserved for a privileged circle, we must not shut our eyes to the fact that the great importance attached to abstract meditation in the Buddhist system could not fail in the end to encourage the growth of mystical ideas. Furthermore, it is undeniable that such ideas were, in some countries, carried to the most extravagant extremes. Efforts to induce a trance-like or hypnotic condition, by abstracting the thoughts from all bodily influences, by recitation of mystical sentences, and by superstitious devices for the acquisition of supernatural faculties, were placed above good works and all the duties of the moral code. We might point, too, to the strange doctrine which arose in Nepāl and Tibet—the doctrine of the Dhyāni-Buddhas (or ‘Buddhas of Meditation’)—certain abstract Essences existing in the formless worlds of thought, who were held to be ethereal and eternal representatives of the transitory earthly Buddhas. These have been adverted to in a previous Lecture (see p. 202). Our present concern is rather with the growth and development of mystical Buddhism in India itself, through its connexion with the system of philosophy called Yoga and Yogāćāra. The close relationship of Buddhism to that system is well known; but the various practices included under the name Yoga did not owe their origin to Buddhism. They were prevalent in India before Gautama Buddha’s time; and one of the most generally accepted facts in his biography is that, after abandoning his home and worldly associations, he resorted to certain Brāhman ascetics, who were practising Yoga. What then was the object which these ascetics had in view?