It appears when, instead of yielding up the whole of my gaze to the world, I turn towards this gaze itself, and when I ask myself what precisely it is that I see; it does not occur in the natural transactions between my sight and the world, it is the reply to a certain kind of questioning on the part of my gaze, the outcome of a second order or critical vision which tries to know itself in its own particularity, of an 'attention to the pure visual', which I exercise either when I am afraid of being mistaken, or when I want to undertake a scientific study of the spectacle presented.