2. _Period of Literary Production_ (1813–1831). In 1813 he wrote the _Four-fold Root of the Principle of Sufficient Reason_, in the Thuringian forest, when other German young men were rallying to arms against Napoleon. This was accepted as a doctorate thesis at Jena. From 1814 to 1819 he lived in Dresden at work on _The World as Will and Idea_, which is the complete exposition of his doctrine. The work is divided into four parts: 1. Theory of Knowledge; 2. Description of the Forms of the Will; 3. Art as a Deliverance from the Will; 4. Morality as a Deliverance from the Will. In 1820 he got a position as Privat-docent in the University of Berlin. This was the only year of his teaching and was an utter failure. 3. _Period of Retirement_ (1831–1860). In 1831 he went to Frankfort-on-the-Main to live alone and in retirement. Slowly he became known and gathered a little circle of disciples about him. He died in 1860. =The Influences upon Schopenhauer’s Thought.= The principal influences upon Schopenhauer’s thought were three: (1) Kant, from whom he got his transcendental theory of knowledge (he always considered himself to be Kant’s true heir); (2) Plato, from whom he got his formulation of eternal Ideas as offering an escape from the Will; (3) the Hindus, from whom he got his ethical-Mysticism and the confirmation of his pessimism. Schopenhauer is unique among the philosophers of Europe, because he denied all for which the Enlightenment stood. Even such reactionaries against the Enlightenment as Rousseau were a part of its essential spirit; for the presupposition of traditional theology and philosophy has been that existence is essentially a harmony. Schopenhauer, however, appealed to the discordances and the sorrow of existence, and drew the inference that fundamentally existence is irrational. For the source of Schopenhauer’s unique teaching we have to look, therefore, farther than modern Europe. The preceding modern European philosophers whom we have studied, developed their philosophies from purely Occidental sources. Schopenhauer drew from the Orient as well as from the Occident. The Romanticists had re-discovered Orientalism. The study of the Hindus had been interesting European scholars since the beginning of the nineteenth century. Schopenhauer, who was introduced to Indian philosophy by Goethe’s friend, Fr. Mayer, read the Upanishads in a Latin translation; and they contributed much to the development of the theory which his own emotional and cynical nature had presaged. The Hindus had long felt that the main problem of existence is moral and physical evil. Schopenhauer found in this teaching the statement of his own attitude.