Like all magical mysteries, the secrets of the Great Work have a triple meaning: they are religious, philosophical and natural. Philosophical gold in religion is the Absolute and Supreme Reason; in philosophy, it is truth; in visible nature, it is the sun: in the subterranean and mineral world, it is the purest and most perfect gold. Hence the search after the Great Work is called the Search for the Absolute, and this work itself is termed the operation of the sun.