Surfaces play an important role in visual perception. They are perceived as ‘(perceptual) reliefs’. that are surfaces in 2 + 1D perceptual space, that is the product space of the 2D visual field and the ID ‘depth dimension’. It is in many respects irrelevant whether the observer views a true 3D scene or a flat (2D) picture of a scene. In both cases, the percepts are reliefs in 2 + ID perceptual...

I RISE NOW TO SPEAK with the assumption that all of you know very well what, I am going to say. I am the humanist here, the professor of English. We humanists, when asked to speak on questions of science and technology, arc notorious for offering an embarrassed and ignorant respect toward those matters, a respect, however, which can all too quickly degenerate into insolent condescension. Face t...