Eliphas Levi’s Duad

From: Eliphas Levi, Transcendental Magic, A.E.Waite, Chicago, 1910:

BOAZ and JAKIN are the names of the two symbolical Pillars before the principal entrance of Solomon's Kabalistic Temple. In the Kabalah these Pillars explain all mysteries of antagonism, whether natural, political or religious… The active principle seeks the passive principle, the plenum desires the void, the serpent's jaw attracts the serpent's tail… The monad can manifest only by the duad; unity itself and the notion of unity at once constitute two. The unity of the Macrocosm reveals itself by the two opposite points of two triangles… To make light visible God had only to postulate shadow. To manifest the truth He permitted the possibility of doubt. The shadow bodies forth the light, and the possibility of error is essential for the temporal manifestation of truth.