F. C. Happold was one of the most convincing writers on mysticism and esoteric subjects. He was a schoolmaster and headmaster most of his life, apart from his service in the first world war in which he won the Distinguished Service Order.

His most famous book was Mysticism: A Study and an Anthology, which was published by Penguin in 1963. Here are a couple of passages I like from his Perennial Philosophy (1970):

What is mysticism? The word “mystic” has its origin in the Greek mysteries. A mystic was one who had been initiated into these mysteries, through which he had gained an esoteric knowledge of divine things and been “reborn into eternity”. His object was to break through the world of history and time into that of eternity and timelessness. […]

In the world, constituted as it is, men are faced not with one single truth but with several “truths”, not with one but with several pictures of reality. They are thus conscious of a “discord in the pact of things”, whereby to hold to one “truth” seems to be to deny another. One part of their experience draws to one, another to another. It has been the eternal quest of mankind to find the one ultimate Truth, that final synthesis in which all partial truths are resolved. It may be that the mystic has glimpsed this synthesis.