I was honoured to have received a comment from Richard Johns on my blog post about his "Self Organization" paper . I have reproduced Richard’s comment and my reply below. I have also added some further remarks:
Hi Timothy,
Thanks for your detailed treatment of my paper -- actually the best I have seen.
The objection you raise is a good one, although I think it can be answered. (Jeffrey Shallit made the same point in an email to me.)
There are simple (i.e. short) algorithms that can generate irregular strings, as I define them. You mention pseudo-random sequences, and I have previously thought about the digits of Pi. Hence these things are algorithmically simple, despite their irregularity.
As I pointed out to Shallit, I claim that irregular objects are *dynamically* complex, not *algorithmically* complex. And, while it seems certain that dynamically simple objects are algorithmically simple (since dynamical systems can be emulated by computers) the converse is far less obvious. In other words, while the digits of Pi can be generated by a short program, it might not be produceable easily within a dynamical system, from a random initial state.
If a converse theorem does hold, however (i.e. algorithmically simple objects are dynamically simple) then my arguments have gone wrong somewhere. But even in that case, self-organisation theories of evolution will be in a difficult position. For they will then be committed to the claim that living organisms are algorithmically (and dynamically) simple. In other words, living organisms are like Pi, merely *appearing* to be complex, while in fact being generated by a very short program. (Vastly shorter than their genomes, for example.)
Following Richard Dawkins, who coined the term "designoid" for an apparently designed object, one might say that living organisms are "complexoid". While perhaps not obviously false, this view is likely to be very unattractive.
My reply now follows:
Thanks for the comment Richard,
I am not sure I understand what you mean by producing an object *dynamically* as opposed to *algorithmically*. In your paper you seem to be using a cellular automata model to generate your objects. No problems with that except that as far as I understand, cellular automata can be simulated algorithmically and therefore fall under the algorithmic category. Moreover, if Stephen Wolfram’s work is anything to go by (and some of my own work), cellular automata also generate complex “Pi” like patterns pretty quickly – complex in the sense you have defined in your paper; that is they show a high irregularity or “disorder” as I call it.
Now this doesn’t mean to say, of course, that life actually is the product of a clever dynamics, but given both your definition of irregularity and your use of an algorithmic cellular automata model, it seems we are back to square one – we haven’t yet succeeded in eliminating self organization from the inquiry. However, for reasons I have given in this blog entry I can see why a “soft focus” version of your limitative theorem applies. But given that the resources of an Intelligent Designer is within my particular terms of reference, then it seems not outside the bounds of possibility that should the required fruitful self organizing regime actually be a mathematically possibility, then that intelligence is capable of contriving it.
If (repeat if) this is the case then it is wrong to conclude that life must therefore be algorithmically simple for this reason: The space of all possible algorithms, though a lot smaller than the space of all possible configurations, is still a very, very large space as far as we humans are concerned. I suspect (and this is only a hunch) that not any old algorithm has the right Self Organising properties required to generate living things - in which case selecting the right algorithm is then a computationally complex task; that is, life is not algorithmically simple in absolute terms.
One more thing: Imagine that you were given the problem of Pi in reverse; that is you were given the pattern of digits and yet had no clue as to what, if any, simple algorithm generated it. The hard problem then is to guess the algorithm – generating Pi after you have found the algorithm is the easy problem. So to me life remains algorithmically complex even if it’s a product of SO.
SOME FURTHER REMARKS
ONE) I am still not sure just how Richard defines the word “dynamic”. The only thing I have to go on is that he drew his conclusions from a cellular automata model, which I assume is his understanding of a dynamic system (?). Wolfram’s cellular system is effectively just another model of computation and therefore I guess that it would be possible to program cellular automata to calculate Pi; such a program is likely to be “simple” in as much as it is likely to have a short length, a short execution time and start with a simple initial state. Therefore I cannot make sense of what Richard means by suggesting that Pi is likely to be dynamically complex, but algorithmically simple.
TWO) I conclude therefore, that Pi can be “easily” generated within a dynamical system. However, Richard actually says this: “In other words, while the digits of Pi can be generated by a short program, it might not be produceable easily within a dynamical system, from a random initial state.” That last phrase, “from a random initial state”, is crucial as it rescues Richard’s statement: If the algorithm is the sort where the initial state and the corresponding output have a one to one mapping then most initial conditions will not lead to Pi in a realistic time. Therefore a random initial state is very unlikely to lead to Pi being calculated in a realistic time.

"I only employ chimps, but to get a result I need a lot of them"
FIVE) Unless one subscribes to some kind of multiverse/infinite trial system, even bog standard evolution, if it is to work, must be resourced by improbable preconditions. This improbability has the effect of triggering Demsbki’s design detection criterion and thus in the abstract evolution has the imprimatur of Intelligent Design. However, the ID community represented by Uncommon Descent are defacto anti-evolutionist and therefore they will do their damndest to try and show evolution to be a mindless process that simply doesn’t work; anyone who so much as entertains evolution as a viable “self organizing” candidate is likely to be accused of courting “naturalism” and perhaps even accused of failing a crucial faith test. The irony is that they, along with the militant atheists, seem to have subliminally bought into the deistical intuition that “well oiled” mathematical mechanisms need no divine support or perhaps not even a divine initiator. (See my blog post here)
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