Light requires dark, therefore all opposites require each other.

from Dialogue of the Saviour by New Testament apocrypha nonfiction ~2 min read

Judas responded, saying, "Tell me, Lord, how it is that [...] which shakes the earth moves." 
The Lord picked up a stone and held it in his hand, saying "What am I holding in my hand?" 
He said, "It is a stone." 
He said to them, "That which supports the earth is that which supports the heaven. When a Word comes forth from the Greatness, it will come on what supports the heaven and the earth. For the earth does not move. Were it to move, it would fall. But it neither moves nor falls, in order that the First Word might not fail. For it was that which established the cosmos and inhabited it, and inhaled fragrance from it. For [...] which do not move, I [...] you, all the sons of men. For you are from that place. In the hearts of those who speak out of joy and truth, you exist. Even if it comes forth in the body of the Father among men, and is not received, still it [...] return to its place. Whoever does not know the work of perfection, knows nothing. If one does not stand in the darkness, he will not be able to see the light. If one does not understand how fire came into existence, he will burn in it, because he does not know the root of it. If one does not first understand water, he knows nothing. For what use is there for him to be baptized in it? If one does not understand how blowing wind came into existence, he will blow away with it. If one does not understand how body, which he bears, came into existence, he will perish with it. And how will someone who does not know the Son know the Father? And to someone who will not know the root of all things, they remain hidden. Someone who will not know the root of wickedness is no stranger to it. Whoever will not understand how he came will not understand how he will go, and he is no stranger to this cosmos which will [...], which will be humiliated."

—New Testament apocrypha, Dialogue of the Saviour, p. -1