What we really want to see is hidden behind the cover. The covering cannot be removed because it is not a real thing, it only exists in our thinking and imagination. There is a close relationship between vision and experience, even the "unthinking association" in an unconscious state. To some extent, the image of an object is automatically connected to experience from the moment we see it. When you see a glass, you know it is a glass because it comes from the brain's empirical judgment, not depending on your visual image. Even if only a part of the glass is exposed, you can still roughly judge what it is, but you cannot be specific to every detail. The brain cannot stop "seeing" until it finds a satisfactory answer.