Intellectually, perspective [drawing] is a breakthrough, because here, for the first time, the physical space we live in is being depicted as ifit were an abstract, mathematical space. A less obvious innovation due to perspective is that here, for the first time, people are actually drawing pictures of infinities.

A computation is a process that obeys finitely describable rules.

What is the shape of space? Is it flat, or is it bent? Is it nicely laid out, or is it warped and shrunken? Is it finite, or is it infinite? Which of the following does space resemble more: (a) a sheet of paper, (b) an endless desert, (c) a soap bubble, (d) a doughnut, (e) an Escher drawing, (f) an ice cream cone, (g) the branches of a tree, or (h) a human body?

Electronic distribution is more of a fall-back strategy for putting out a book that isn't deemed profitable enough to print. You hardly make any money publishing an electronic book.

The churning of a human mind is unpredictable, as is the anatomy of the human heart.

If we suppose that many natural phenomena are in effect computations, the study of computer science can tell us about the kinds of natural phenomena that can occur.

But how does it feel to plug into a system that's say, a million times as smart as a person.