The dark to the light and light to the dark. Always present, always adjacent, seldom spotted. The mysteries revolving within every soul, and the plaster they put on for the society. The dichotomy of seen and unseen, that is what makes the whole. And nature, always treating both the same. A lay eye, would miss the dark often, thinking that light is the only truth. But that's thinking like a caveman who's only seen fire and never gone outside the cave to see sunlight. He would never believe such a thing exists. More importantly he would never see the world completely.
Even physics tells us about dark matter, antimatter that exists in plain sight, but never visible. The current day and age is based on visual sensory perception. This is mostly manufactured and seldom vetted for veracity. We remain in filter bubbles of light, never realising the dark is being hidden from us. We buy the Instagram influenzas for what they propagate without thinking of the nexus of advertisers and businesses that run the show.
Dualism is the essence of nature. Unawareness about it is ignorance. Negating it is ignorance running on denseness.