The Principle of correspondence represents
the Hermetic axiom 'As above, so below, as below, so above' indicating an analogy
between the various planes of being and life, it also reflects the Arcane principle
'From One know All'. It says as much that all planes of being funcion after the same
rules and patterns, and thus the unknown can be comprehended by the knowledge of the
Before you now jump to the conclusion that there is no unknown anymore since you can easily conclude from the known etc. etc., ask yourself how *known* the known really is. For example, ask a row of people what a television set is - you can be well sure that everybody will readily know this. Then ask them to explain how exactly a television set works...
From the Kybalion:
This Principle embodies the truth that there is always a Correspondence between the laws and phenomena of the various planes of Being and Life. The old Hermetic axiom ran in these words: 'As above, so below, as below, so above.' And the grasping of this Principle gives one the means of solving many a dark paradox, and hidden secret of Nature.
There are planes beyond our knowing, but when we apply the Principle of Correspondence to them we are able to understand much that would otherwise be unknowable to us. This Principle is of universal application and manifestation, on the various planes of the material, mental, and spiritual universe - it is an Universal Law.
The ancient Hermetists considered this Principle as one of the most important mental instruments by which man was able to pry aside the obstacles which hid from view the Unknown. Its use even tore aside the Veil of Isis to the extent that a glimpse of the face of the goddess might be caught. Just as a knowledge of the Principles of Geometry enables man to measure distant suns and their movements, while seated in his observatory, so a knowledge of the Principle of Correspondence enables Man to reason intelligently from the Known to the Unknown. Studying the monad, he understands the archangel.