Answer
Rene Guénon (1886-1951) was a French metaphysician and esotericist. He is considered a representative of philosophia perennis, along with Frithjof Schuon. Guénon argued that there is a perennial philosophy that is found in all religions and philosophies. He also argued that the modern world is in a state of decline and that the only way to save it is to return to the perennial philosophy.