structural:reformatting, information:extraction
Indology

Schopenhauer read the Latin translation of the ancient Hindu texts, the Upanishads, translated by French writer Anquetil du Perron from the Persian translation of Prince Dara Shukoh entitled Sirre-Akbar ("The Great Secret"). He was so impressed by its philosophy that he called it "the production of the highest human wisdom", and believed it contained superhuman concepts. Schopenhauer considered India as "the land of the most ancient and most pristine wisdom, the place from which Europeans could trace their descent and the tradition by which they had been influenced in so many decisive ways", and regarded the Upanishads as "the most profitable and elevating reading which is possible in the world. It has been the solace of my life, and will be the solace of my death."

Schopenhauer was first introduced to Anquetil du Perron's translation by Friedrich Majer in 1814. They met during the winter of 1813–1814 in Weimar at the home of Schopenhauer's mother, according to the biographer Safranski. Majer was a follower of Herder, and an early Indologist. Schopenhauer did not begin serious study of the Indic texts until the summer of 1814. Safranski maintains that, between 1815 and 1817, Schopenhauer had another important cross-pollination with Indian thought in Dresden. This was through his neighbor of two years, Karl Christian Friedrich Krause. Krause was then a minor and rather unorthodox philosopher who attempted to mix his own ideas with ancient Indian wisdom. Krause had also mastered Sanskrit, unlike Schopenhauer, and they developed a professional relationship. It was from Krause that Schopenhauer learned meditation and received the closest thing to expert advice concerning Indian thought.

The view of things that all plurality is only apparent, that in the endless series of individuals, passing simultaneously and successively into and out of life, generation after generation, age after age, there is but one and the same entity really existing, which is present and identical in all alike;—this theory, I say, was of course known long before Kant; indeed, it may be carried back to the remotest antiquity. It is the alpha and omega of the oldest book in the world, the sacred Vedas, whose dogmatic part, or rather esoteric teaching, is found in the Upanishads. There, in almost every page this profound doctrine lies enshrined; with tireless repetition, in countless adaptations, by many varied parables and similes it is expounded and inculcated.

For Schopenhauer, will had ontological primacy over the intellect; desire is prior to thought. Schopenhauer felt this was similar to notions of puruṣārtha or goals of life in Vedānta Hinduism.

In Schopenhauer's philosophy, denial of the will is attained by:

The book Oupnekhat (Upanishad) always lay open on his table, and he invariably studied it before going to bed. He called the opening up of Sanskrit literature "the greatest gift of our century", and predicted that the philosophy and knowledge of the Upanishads would become the cherished faith of the West. Most noticeable, in the case of Schopenhauer's work, was the significance of the Chandogya Upanishad, whose Mahāvākya, Tat Tvam Asi, is mentioned throughout The World as Will and Representation.