Contrast is the basis of distinct experiences. Of course, the only way you ever understand light is that you can compare it to darkness. Close your eyes and you experience darkness. Open your eyes and you experience light again.
Now imagine you’ve never experienced light before—and that all you’ve ever known is darkness. Imagine someone trying to describe light to you. Would you understand what they’re saying? Would the description make any sense to you? Imagine you’ve never known light before. Would it make sense to hear someone trying to describe darkness?