as bizarrely different from human intelligence as many of the simple programs in this book are different from the systems that have traditionally been studied in human mathematics and science.

Implications for Technology

My main purpose in this book has been to build a new kind of basic science. But I expect that in time what I have done will also have many implications for technology. No doubt there will be all sorts of specific applications of particular results and ideas. But in the long run probably the most important consequence will be to introduce a vast new range of systems and processes that can be used for technology.

And indeed one of the things that emerges from this book is that traditional engineering has actually considered only a tiny and quite unrepresentative fraction of all the kinds of systems and processes that are in principle possible.

Presumably the reason—as I have mentioned several times in this book—is that its whole methodology has tended to be based on setting up systems whose behavior is simple enough that almost every aspect of them can always readily be predicted. But doing this has immediately excluded many of the systems that I have studied in this book—or for that matter that occur in nature. And no doubt this is why systems created by engineering have in the past usually ended up looking so much simpler than typical systems in nature.

And with traditional intuition it has normally been assumed that the only way to create systems that show a higher degree of complexity is somehow to build this complexity into their underlying rules.

But one of the central discoveries of this book is that this is not the case, and that in fact it is perfectly possible for systems even with extremely simple underlying rules to produce behavior that has immense complexity—and that looks like what one sees in nature.

And I believe that if one uses such systems it is almost inevitable that a vast amount of new technology will become possible.

There are some places where just the abstract ability to produce complexity from simple rules is already important. One example discussed in Chapter 10 is cryptography. Other examples include all