Everything we see hides another thing, we always want to see what is hidden by what we see. There is an interest in that which is hidden and which the visible does not show us. This interest can take the form of a quite intense feeling, a sort of conflict, one might say, between the visible that is hidden and the visible that is present.
The feeling we experience while we look at a picture is not to be distinguished from the picture or from ourselves. the feeling, picture, and ourselves are united in one mystery.