"Just over twenty years ago I made what at first seemed like a small discovery: a computer experiment of mine showed something I did not expect. But the more I investigated, the more I realized that what I had seen was the beginning of a crack in the very foundations of existing science, and a first clue towards a whole new kind of science.

This book is the culmination of nearly twenty years of work that I have done to develop that new kind of science. I had never expected it would take anything like as long, but I have discovered vastly more than I ever thought possible, and in fact what I have done now touches almost every existing area of science, and quite a bit besides."

Preface · The Foundations for a New Kind of Science · The Crucial Experiment · The World of Simple Programs · Systems Based on Numbers · Two Dimensions and Beyond · Starting from Randomness · Mechanisms in Programs and Nature · Implications for Everyday Systems · Fundamental Physics · Processes of Perception and Analysis · The Notion of Computation · The Principle of Computational Equivalence · Notes · Index