It All Comes Down to

It All Comes Down To B_NEW \Leftarrow B_0 \oplus (B_1 \vee B_2)The formula in the title is the binary version of the rule 30 from Stephen Wolfran's new book,A New Kind of Science (Wolfram Media, 2002) Rule 30is a cellular automation that looks at three bits and generates a new one, B_NEW, from those three.It is said to generatepatterns that are complex and indistinguishable from random ones, a remarkable result for such a simple algorithm. As of this writing, Amazon.com ranks Wolfram's book number 18 in sales of all books. To put this in perspective, I checked the rank of the Feynman lectures (Addison-Wesley,1970), which was 2,003,and of Marc Kac's little masterpiece, Statistical Independence in Probability Analysis and Number Theory (Mathematical Assoc.of America,1959), which was 1,040,441 .Even if the sales figures were less impressive, a scientific book whose central premise is that the universe is an algorithm is bound to be of great interest to anyone concerned with computational science and engineering, and many other people as well. This issue of CiSE contains two reviews of A New Kind of Science. My purpose here is to make a few remarks about the directions this new science might take.