The 5 classical elements that make of the universe: Fire, Air, Water, Earth, & Spirit.
Of these Fire and Water oppose each other, as do Air and Earth. So what is Spirit opposing?
Each culture seemed to have its own list but said list usually had 4 or 5 elements. I propose a more complex system. Still we have Earth/Air, Fire/Water, & Spirit(life). But we had in the opposing elements of Light and Shadow, and the opposing element of Spirit, Death. And in my philosophy death is actually a rebirth & reincarnation, so for those that the idea of Death as an element maybe we could say Rebirth, but that sounds less in opposition to Spirit.
So in my outlook on the universe there are 8 elements that form everything. Sometimes they work together to create things and sometimes they oppose each other. The important thing to remember always is balance. The Universe always seeks balance in the long run.