The German philosopher Arthur Schopenhauer read the Latin translation and praised the Upanishads in his main work, The World as Will and Representation (1819), as well as in his Parerga and Paralipomena (1851).[199] He found his own philosophy was in accord with the Upanishads, which taught that the individual is a manifestation of the one basis of reality. For Schopenhauer, that fundamentally real underlying unity is what we know in ourselves as "will". Schopenhauer used to keep a copy of the Latin Oupnekhet by his side and commented,
In the whole world there is no study so beneficial and so elevating as that of the Upanishads. It has been the solace of my life, it will be the solace of my death.[200]
Schopenhauer's philosophy influenced many famous people and introduced them to the Upanishads. One of them was the Austrian Physicist Erwin Schrödinger, who once wrote:
“There is obviously only one alternative,” he wrote, “namely the unification of minds or consciousnesses. Their multiplicity is only apparent, in truth there is only one mind. This is the doctrine of the Upanishads.”[201]
Another German philosopher, Friedrich Wilhelm Joseph Schelling, praised the ideas in the Upanishads,[202] as did others.[203] In the United States, the group known as the Transcendentalists were influenced by the German idealists. Americans, such as Emerson and Thoreau embraced Schelling's interpretation of Kant's Transcendental idealism, as well as his celebration of the romantic, exotic, mystical aspect of the Upanishads. As a result of the influence of these writers, the Upanishads gained renown in Western countries.[204]
The poet T. S. Eliot, inspired by his reading of the Upanishads, based the final portion of his famous poem The Waste Land (1922) upon one of its verses.[205] According to Eknath Easwaran, the Upanishads are snapshots of towering peaks of consciousness.[206]
Juan Mascaró, a professor at the University of Barcelona and a translator of the Upanishads, states that the Upanishads represents for the Hindu approximately what the New Testament represents for the Christian, and that the message of the Upanishads can be summarized in the words, "the kingdom of God is within you".[207]
Paul Deussen in his review of the Upanishads, states that the texts emphasize Brahman-Atman as something that can be experienced, but not defined.[208] This view of the soul and self are similar, states Deussen, to those found in the dialogues of Plato and elsewhere. The Upanishads insisted on oneness of soul, excluded all plurality, and therefore, all proximity in space, all succession in time, all interdependence as cause and effect, and all opposition as subject and object.[208] Max Müller, in his review of the Upanishads, summarizes the lack of systematic philosophy and the central theme in the Upanishads as follows,
There is not what could be called a philosophical system in these Upanishads. They are, in the true sense of the word, guesses at truth, frequently contradicting each other, yet all tending in one direction. The key-note of the old Upanishads is "know thyself," but with a much deeper meaning than that of the γνῶθι σεαυτόν of the Delphic Oracle. The "know thyself" of the Upanishads means, know thy true self, that which underlines thine Ego, and find it and know it in the highest, the eternal Self, the One without a second, which underlies the whole world.
— Max Müller
