The Traditionalist School was founded in its current form by the French metaphysician René Guénon, although its precepts are considered to be timeless and to be found in all authentic traditions. It is also known as Perennialism, the Perennial Philosophy, or Sophia Perennis, and as a philosophy it is known by Aristasians as Essentialism. The term Philosophia Perennis goes back to the Renaissance, while the Hindu expression Sanatana Dharma - Eternal Doctrine - has precisely the same signification.

The other founding figures of the Traditionalist School were Ananda Coomaraswamy, the Ceylonese scholar and the Swiss Mystic Frithjof Schuon. To these were added over time such imposing figures as Titus Burckhardt, Martin Lings, Gai Eaton and Professor Seyyed Hossein Nasr. Other major figures of the twentieth century have been profoundly influenced by the school, including T.S. Eliot, the Romanian anthropologist Mircea Eliade and the Italian esotericist and political thinker Julius Evola.

The fundamental tenets of this school or philosophy may be stated as follows:

1. All authentic religious traditions are true, deriving from the Primordial Tradition. Guénon's work draws extensively on Hindu, Taoist, Moslem, Judaic, Christian and Masonic sources. At first, following certain Hindu schools, he rejected Buddhism as heretical, but Dr. Coomaraswamy, at the instigation of Marco Pallis (a Traditionalist convert to Tibetan Buddhism) demonstrated the essential orthodoxy of Buddhism and its consistency with Vedanta. Guenon, accordingly, authorised amendments to references to Buddhism in his earlier works.
2. Contrary to the modern idea of "progress", and in accordance with all traditions, the world is in a state of intellectual and spiritual decline, inevitable from the very start of an historical cycle. We are present in what the Classical West called the Age of Iron, and the Hindus Kali Yuga.

In addition to this, the Western world, unlike other cultures, has lost its connection to the Primordial Tradition. This took place first in the Classical era, was rectified by Christianity, which re-introduced a modified form of the Primordial Tradition, but the severance began again at the time of the renaissance (this is a somewhat truncated account. The reader is referred to Guénon's Crisis of the Modern World for a fuller one).

The Aristasian theorist, Alice Lucy Trent has elaborated the theory further by an application of the Hindu science of the three Gunas to the process of the Western history of the past millennium, accounting for both the descent into "modernism" at the time of the renaissance and the "post-modernist cultural collapse" of the twentieth century. (Vide The Feminine Universe, by A.L. Trent).

In accordance with the two preceding positions, Traditionalists accord a high value to the intellectual activities of the pre-modern world and non-Western societies, and a good deal of their work lies in the sciences of metaphysics and symbolism, as well as the discussion and elucidation of the various spiritual traditions. Where they venture into such realms as social criticism it is clearly from a Traditionalist perspective which turns the Progressist/Evolutionist assumptions of modernist theorists (both "left" and "right"), and of post-modernists alike, on their heads.

A recent history of the Traditionalist School and its influence in various different spheres and countries has been written by Dr. Mark Sedgewick under the title Against the Modern World.