Entropy is not about speeds or positions of particles, the way temperature and pressure and volume are, but about our lack of information.

This is not what I thought physics was about when I started out: I learned that the idea is to explain nature in terms of clearly understood mathematical laws; but perhaps comparisons are the best we can hope for.

For generations, field guides to plants and animals have sharpened the pleasure of seeing by opening our minds to understanding. Now John Adam has filled a gap in that venerable genre with his painstaking but simple mathematical descriptions of familiar, mundane physical phenomena. This is nothing less than a mathematical field guide to inanimate nature.

Science has taught us that what we see and touch is not what is really there.

If quantum communication and quantum computation are to flourish, a new information theory will have to be developed.

To put it one way, a collection of Shakespeare's plays is richer than a phone book that uses the same number of letters; to put it another, the essence of information lies in the relationships among bits, not their sheer number.

Entropy is not about speeds or positions of particles, the way temperature and pressure and volume are, but about our lack of information.