From Complexity to Perplexity

The June 1995 Scientific American includes an article From Complexity to Perplexity by John Horgan. Subtitled ``Can science achieve a unified theory of complex systems? Even at the Sante Fe Institute, some researchers have their doubt'' the article is very critical of artificial life and related disciples. I highly recommend it. Below I excerpt some points, and comment on them, [concluding what?]

Building computer models of natural systems is in vogue all over science. An `applied computer science' where the principles of the implementation and analysis of models of complex systems are studied is useful. To what extent can one perform an experiment with the model instead of the real thing?

How is the field of complexity any different from numerical analysis?

What kind of general principles and unified theories are the immodest talking about? I don't know. If they think they can formalize (compile away) layers of complexity, they are indeed wrong. Murray Gell-Mann, a founder of the SFI makes some claims in his book The Quark and the Jaguar.

This is one of several swipes at math. I can see the point: the mathematician solves equations and proves theorems. The problem is disposed of and we move onward. It's silly to suggest this will happen to trade balances, mental health, viruses, etc.

Yes, absolutely. Compexity is relative to an observer (see here). That doesn't mean that it is an unfit target of science---everything is at least a little relative (except maybe math).

All phenomena in the world are the result of simple rules: the field equations of quantum physics. Sometimes complexity appears in a `single level' from many applications of simple rules over a simple system, the kind of thing we can model. Such layers are the subject of complexologists. Surely many `natural systems' of the world are `big balls of complexity' with no layers and no hope of an efficient model. But the general success of scientific models demonstrates that important systems lie within the scope.

So what? Who claims otherwise? This repeats the above error of throwing out complexity because it has been `polluted' with relativism. As if the rest of science stood on firm ground...

Do you trust the Turing test? If it quacks...

I think there's something to this; that is one of the meanings of the word `pink' in bomb's iconic language.

Yes. And just like there's a theorem behind the bell curve (the Strong Law of Probability), perhaps there's a theorem behind Power law behavior.

New laws are only needed because of our limited mental capacity. complex systems are exactly those things that defy ability to relate both ends. If there's really anything new at any level, then this is evidence of a god.

One reason that there are more simple systems than you might expect or guess is that a simple system can appear on top of a complex system, if we use a shoe-horn, idealizing the complex. Thus weather simulations can work by idealizing the atmosphere, or a population dynamics system by idealizing reproducing individuals, a neural net with Hebbs neurons, or genes, or... Is it really `simple'? Is it a scientific model? it can't work just right because we've thrown out some information, but it might work well enough to be useful.

See Gould's Natural History.


Yes! I do not believe the life force exists like gravity or magnetism. It's more like statistics, perhaps the Strong Law. Of course Kauffman's `similar to ours' is meaningless. I'm not too familiar with the term, but `extropy' sounds about right.

there's no doubt that more powerful computers will allow better modeling and the benefits thereof. Even though we may never `understand' one of our models---because it's complex beyond our minds, its still useful! Our perplexity is really wonderment that `that's all there is to it'.