Wednesday, March 04, 2009

Teleology vs Teleonomy: Can a "Program" Exist Before Its "Programmer"?


This post is a follow-up to the previous post on the subject of the "randomness" in the processes that generate the variation that is necessary for biological evolution.

Can a "program" exist before its "programmer" (and therefore bring it into being)? This seems to be the core of the disagreement between ID supporters and mainstream scientists. The former (which include Charles Darwin's very close friend, Asa Gray) advocate the idea that the variation upon which natural selection and other evolutionary processes work is neither random nor unintentional. The latter (which include Darwin and his intellectual heirs) do not disagree with the idea that such variation is not "random". What they disagree with is the idea that there is some "intention" or "plan" guiding the variation that occurs, so that certain outcomes (including, but not limited to, the origin of humans) are more likely than others.

To answer the question that stands at the head of this post, I think it's essential to emphasize (as I did in the original blogpost) that the terms “foresighted” and “goal-oriented” are not equivalent, nor are the processes to which they are applied. As I have pointed out in many posts, there is no inherent contradiction between a process being purely "natural" (i.e. the result of the operation of purely natural processes) and being "goal-oriented".

Ernst Mayr (surely no advocate of "intelligent design") argued forcefully (and, in my opinion, convincingly) that biological organisms are indeed "goal-oriented". That is, their genomes provide a program, the function of which is to bring about a particular state of affairs: the survival and reproduction of the organism via its interactions with its environment.

The origin of the genome (i.e. the "program" itself) is an entirely different situation, however. Ever since Darwin it has been a standard assumption that the evolutionary processes by which the genetic "programs" that direct the assembly and operation of living organisms are not goal-oriented. These evolutionary processes – natural selection, sexual selection, founder effects, genetic bottlenecks, neutral "drift" in deep evolutionary time, exaptation, heterochronic development, changes in homeotic development, interspecific competition, species-level selection, serial endosymbiosis, convergence/divergence, hybridization, phylogenetic fusion, background and mass extinction/adaptive radiation, and internal variance – do not require any kind of "goal orientation" to produce the living entities and processes we observe around and within us. And, since such processes do not require goal-orientation or intentionality, these are not included in evolutionary explanations. Some, but not all, evolutionary biologists extend this idea to the assumption that goal-orientation or intentionality do not exist in nature, in the absence of pre-existing genomic "programs").

The main reason for this assumption has been that it is extremely problematic to agree on how one would go about showing that the aforementioned evolutionary processes have indeed been goal-oriented. The most serious objection to this idea is that there seems to be nowhere for such a "directing agency" to exist in material form, nor any natural means by which its goals could be impressed upon physical organisms.

The genomes of organisms are physical/chemical "stuff", which is translated via physical/chemical "machinery" into biological entities and processes. That is, there is a physical/chemical "vehicle" in which the information for assembling and operating organisms is carried and expressed.

The same would not the case for the putative source of the "evolutionary program" which might direct the evolution of the genomes of living organisms. Since such an "evolutionary program" would cause the evolution of the "genomic programs" which direct the assembly and operation of living organisms, such a program would necessarily have to exist before the origin and evolution of biological genomes, as it would be necessary for it to do so to direct their coming into being.

This presents two serious problems:

• By what mechanism(s) would such an "evolutionary program" cause "genomic programs" to come into existence, and

• Precisely where in the physical universe would such a pre-existing "evolutionary program" itself exist?

We seem to have two direct logical contradictions in terms:

• How can a non-natural "evolutionary program" cause a natural "genomic program" to come into existence, and

• How can a programmer pre-exist the program which brings itself into existence?

There is a proposed answer to these two questions, but one which most ID supporters seem loathe to invoke:

• That the "pre-existing program" that directs the evolution of the genomic programs of living organisms is woven into the structure of physical reality itself.

This is the line of inquiry pursued by Ilya Prigogine and Stuart Kauffman (among others), but which is rejected out-of-hand by nearly all ID supporters (most notably Michael Behe, William Dembski, and Phillip Johnson), who prefer a purely "supernatural" source for the "pre-existing program" by which evolution has been directed).

As always, comments, criticisms, and suggestions are warmly welcomed!

--Allen

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Tuesday, May 16, 2006

The Resurrection of Formal and Final Causes



SOURCE: Telic Thoughts

COMMENTARY: Allen MacNeill

Over at Telic Thoughts, g arago commented:

"It would perhaps help to bring in Aristotle's causes again, to the effect that final causes are virtually eliminated from modern science. Postmodernity enables the case for formal causality to re-emerge as a legitimate source of (scientific or non-scientific) knowledge."


It's interesting that this should be proposed, as that is precisely what I will be doing during the very first meeting of my "purpose in nature" seminar at Cornell this summer. It is a sad fact that most undergraduates (and an alarming number of philosophers and scientists) do not know anything about Aristotle's doctrine of causes, nor how they relate to the work they are doing.

Aristotle identified four causes for every phenomenon:

Material Cause: What the object in question is composed of (e.g. a house is composed of boards, bricks, mortar, etc.;

Formal Cause: What formal category the object is an exemplar of (e.g. any particular house is a "house" or dwelling place for people);

Efficient Cause: What immediate processes bring about the existence of the object (e.g. the carpenters, etc. are the efficient cause of the house); and

Final Cause: The purpose of the object (e.g. carpenters et al build houses "in order to" provide dwelling places for people).

In modern science, both formal and final causes are considered to be unnecessary, and are therefore not generally included in scientific explanations of natural objects and processes. However, it is not strictly true that formal causes have been completely eliminated from science. Much of physics, for example, has taken on some of the characteristics of "formal cause" insofar as physical processes are describable and predictable using formal mathematics. This is particularly the case for physicists who believe that actual physical phenomena are "the working out of underlying mathematical relationships."

The same could be said for evolutionary theory insofar as the "modern evolutionary synthesis" initiated R. A. Fisher, J.B.S. Haldane, and Sewall Wright sought to lay a formal mathematical foundation for biological evolution.

The problem for "intelligent design theory" therefore is to show (if possible) that final causes are necessary (i.e. not just psychologically gratifying or theologically convenient) for evolutionary explanations of natural objects and processes. Final causes (or "purposes") are not entirely missing from evolutionary biology, as shown by the work of Colin Pittendrigh, Francisco Ayala, and Ernst Mayr, all of whom debated the appropriateness of teleological language when referring to adapations. However, no evolutionary biologist has resorted to teleological explanations for the existence or operation of natural selection, speciation, evolutionary development, or other central processes in evolution, at least not recently. The reason for such exclusion has not been an antipathy to theologically based explanations per se, but rather the simple fact that teleological explanations for evolutionary processes have been shown repeatedly to be unnecessary, and therefore irrelevant (notice that I did not say "untrue," as "truth" is also irrelevant in this context).

What W. Dembski and M. Behe and other ID theorists have attempted to do (in my opinion, so far unsuccessfully) is to re-integrate teleology into evolutionary processes. The more recent discussion by some ID theorists of "'front-loaded' intelligent design" is simply a reinvention of Aristotelian formal cause, and as such is indistinguishable from classical deism. Neither of these approaches to "design or purpose in nature" has yet been successful as scientific enterprises because they have not been shown to be indispensible to scientific explanations. Until they are, they will not be integrated into mainstream science. While I personally do not believe they can be, I am willing to be shown otherwise by people who use direct empirical evidence and strong inference to show how teleological explanations are necessary for scientific explanations.

--Allen

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