The Perennial Philosophy is an attempt to present the Highest Common Factor of all theologies by assembling passages from the writings of those saints and prophets who have approached a direct spiritual knowledge of the Divine, and who have recorded not only the method of that approach but also the clarity and tranquility of soul they derived from it. Mr. Huxley quotes from the Chinese Taoist philosophers, from the followers of Buddha and Mohammed, from the Brahmin scriptures and from Christian mystics ranging from St. John of the Cross to William Law, giving preference to those writings, often illuminates by genius, which are unfamiliar to the modern reader. He has connected these passages with a commentary of characteristic penetration, which illustrates, elucidates and develops them.