---
title: "A New Kind of Science"
chunk: 3/4
source: "https://en.wikipedia.org/wiki/A_New_Kind_of_Science"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:33:23.585706+00:00"
instance: "kb-cron"
---

Periodicals gave A New Kind of Science coverage, including articles in The New York Times, Newsweek, Wired, and The Economist. Some scientists, including Cosma Shalizi and Scott Aaronson, criticized the book and perceived a fatal flaw—that simple systems such as cellular automata are not complex enough to describe the degree of complexity in evolved systems, and observed that Wolfram ignored the research categorizing the complexity of systems. Although critics accept Wolfram's result showing universal computation, they view it as minor and dispute Wolfram's claim of a paradigm shift. Others found that the work contained valuable insights and refreshing ideas. Wolfram addressed his critics in a series of blog posts.

=== Scientific philosophy ===
A tenet of NKS is that the simpler the system, the more likely a version of it will recur in a wide variety of more complicated contexts. Therefore, NKS argues that systematically exploring the space of simple programs will lead to a base of reusable knowledge. But many scientists believe that of all possible parameters, only some actually occur in the universe. For instance, of all possible permutations of the symbols making up an equation, most will be essentially meaningless. NKS has also been criticized for asserting that the behavior of simple systems is somehow representative of all systems.

=== Methodology ===
A common criticism of NKS is that it does not follow established scientific methodology. For instance, NKS does not establish rigorous mathematical definitions, nor does it attempt to prove theorems; and most formulas and equations are written in Mathematica rather than standard notation. Along these lines, NKS has also been criticized for being heavily visual, with much information conveyed by pictures that lack formal meaning. It has also been criticized for not using modern research in the field of complexity, particularly works on complexity from a rigorous mathematical perspective. And it has been criticized for misrepresenting chaos theory.

=== Utility ===
NKS has been criticized for not providing specific results that are immediately applicable to ongoing scientific research. There has also been criticism, implicit and explicit, that the study of simple programs has little connection to the physical universe and hence is of limited value. Steven Weinberg has pointed out that no real-world system has been satisfactorily explained using Wolfram's methods. Mathematician Steven G. Krantz wrote, "Just because Wolfram can cook up a cellular automaton that seems to produce the spot pattern on a leopard, may we safely conclude that he understands the mechanism by which the spots are produced on the leopard, or why the spots are there, or what function (evolutionary or mating or camouflage or other) they perform?"

=== Principle of computational equivalence (PCE) ===
The principle of computational equivalence (PCE) has been criticized for being vague, unmathematical, and not making directly verifiable predictions. It has also been criticized for being contrary to the spirit of research in mathematical logic and computational complexity theory, which seek to make fine-grained distinctions between levels of computational sophistication, and for wrongly conflating different kinds of universality property. Moreover, critics such as Ray Kurzweil have argued that it ignores the distinction between hardware and software; while two computers may be equivalent in power, it does not follow that any two programs they might run are also equivalent. Others suggest it is little more than a rechristening of the Church–Turing thesis.

=== The fundamental theory (NKS Chapter 9) ===
Wolfram's speculations of a direction toward a fundamental theory of physics have been criticized as vague and obsolete. Scott Aaronson, Professor of Computer Science at University of Texas Austin, also claims that Wolfram's methods cannot be compatible with both special relativity and Bell's theorem violations, and hence cannot explain the observed results of Bell tests.
Edward Fredkin and Konrad Zuse pioneered the idea of a computable universe, the former by writing a line in his book on how the world might be like a cellular automaton, later further developed by Fredkin using a toy model called Salt. It has been claimed that NKS tries to take these ideas as its own, but Wolfram's model of the universe is a rewriting network, not a cellular automaton, as Wolfram himself has suggested a cellular automaton cannot account for relativistic features such as no absolute time frame. Jürgen Schmidhuber has also charged that his work on Turing machine-computable physics was stolen without attribution, namely his idea on enumerating possible Turing-computable universes.
In a 2002 review of NKS, the Nobel laureate and elementary particle physicist Steven Weinberg wrote, "Wolfram himself is a lapsed elementary particle physicist, and I suppose he can't resist trying to apply his experience with digital computer programs to the laws of nature. This has led him to the view (also considered in a 1981 paper by Richard Feynman) that nature is discrete rather than continuous. He suggests that space consists of a set of isolated points, like cells in a cellular automaton, and that even time flows in discrete steps. Following an idea of Edward Fredkin, he concludes that the universe itself would then be an automaton, like a giant computer. It's possible, but I can't see any motivation for these speculations, except that this is the sort of system that Wolfram and others have become used to in their work on computers. So might a carpenter, looking at the moon, suppose that it is made of wood."

=== Natural selection ===
Wolfram's claim that natural selection is not the fundamental cause of complexity in biology has led journalist Chris Lavers to say that Wolfram does not understand the theory of evolution.