A New Kind of Science (book)A New Kind of Science is a book by Stephen Wolfram, published in 2002. It is a broad self-confident and example-laden tour de force through various sciences, whose central thesis is that simple rules can give rise to complex behavior. From that he extrapolates that nature should be modeled by cellular automata rather than by differential equations and that reality should be considered discrete rather than continuous.
The book is directed at the intelligent layperson rather than at specialists, and its statements often remain vague.
The whole universe itself is conjectured to be a cellular automaton (with probably only very few rules). No particular cellular automaton is proposed, and it is speculated how such a model could exist despite Bell's theorem.
The book also claims that all sufficiently-complex systems are essentially of the same complexity, an idea that has long been known in the form of the Church-Turing thesis, and that most systems around us actually reach this limit complexity.
The book starts by classifying many different types of cellular automata. His goal in these early chapters is to try to answer, when, how, and why these systems achieve random complexity. A general conclusion from this first section is that some rare automata with very simple rules have the potential to generate complex and random results.
Wolfram worked on the book from 1992 to 2002. It was self-published. Wolfram has been criticized for not publishing any of these ideas in peer reviewed journals, and for not crediting other scientists whose work he builds on.