I was inspired to build on an earlier post on polarity by these thoughts from a free pdf in the Psychosynthesis Centre: Balancing and Synthesis of the Opposites by psychologist Roberto Assagiol. Quotes are from that document.
Polarity is a universal fact; it is inherent in cosmic manifestation… From the very moment that cosmic manifestation begins to unfold, duality is born. The first fundamental duality is precisely that between manifestation and the Unmanifest. In the process of manifestation the fundamental polarity is that of Spirit and Matter.
We could see existence as the dance between spirit and matter.
… all polarity is a relationship between two elements… as such, it is never absolute, but relative even to a particular pair of opposites: the same element can be positive in its relation to a certain “pole” and negative in its relation to another. An instance of the relativity of the “polar relationships” exists in the fundamental polarity between Spirit and Matter.