In this post I aim to have a go at the heresy of presenting a case for the plausibility of intelligent design as a factor in biological evolution (although ID of an atypical, non-supernatural sort).
In the first part I'll put forward a philosophical argument for the plausibility of ID, building on arguments made in previous posts. Then I'll address some concerns regarding parsimony constraints in explanation. Finally, I'll address how this all relates to science.
The plausibility of ID
The argument goes as follows:
1. Subjective experience exists.
- I take this as self evident.
2. Panexperientialism is a plausible explanation of the relation between experience and the physical world.
- For general arguments regarding panexperientialism ( which I use synonymously with the term 'panpsychism') refer to external links page. Some biologists who have been sympathetic to a panexperientialist position include Sewall Wright and Bernhard Rensch- papers here and here.
3. A plausible form of panexperientialism is that which posits a universal, cosmic subject.
- Refer to posts here, here and here).
4. It is plausible that the universe is 'finely tuned' for life as a consequence of the drive towards differentiation of an anticipative cosmic subject.
- Refer here
5. Given 4, it is also plausible that the drive towards differentiation of an anticipative cosmic subject could be a factor in biological evolution.
I think that if one accepts the first four premises, then the conclusion (5) is fairly uncontentious - if the universe can fine tune itself for life, then it is reasonable to conclude that it could also direct it's further biological evolution. Thus, to argue against the plausibility of ID as presented here it would be necessary to attack those premises.
In my previous post on the fine tuning problem I noted that putative explanations should be both plausible and parsimonious. To this end, I argued that the the inner workings of the postulated cosmic subject should be correlated with the observed physical world as far as possible, and that one could parsimoniously attribute to it an instinctual and anticipative drive towards differentiation. Parsimony and plausibility constraints also apply in relation also apply in relation to arguments for ID. Thus, inferences regarding the cosmic subject's effect on evolution should impute it with as little intelligence or complexity as possible.
I also noted in that post that the major disadvantage which I see in positing a cosmic subject which can anticipate the future is that the physical correlates of the anticipative propensities of the cosmic subject are not observable (or at least have not been observed to date), which goes against the parsimony constraint.
To address this issue further, although the lack of physical anticipatory correlates lessens the appeal of positing an anticipative cosmic subject, I do not think it is fatal to it. A naturalistic explanation can posit unobservables without being fundamentally flawed. For instance, the multiple universes postulated by quantum physicists, string theorists and so forth are inferences which are not directly observable. Also, something may be unobservable in practice but not in principle always unobservable. For instance, perhaps the anticipatory workings of the cosmic subject could be correlated with fluctuations in the vacuum energy of empty space. In this case (and continuing the analogy from the prior post), just as the neural correlates of a jumping dog's anticipative functions are not obviously observable to an undeveloped science, so too the passive workings of the cosmic subject's anticipative functions may not be readily observable, with only its active actions being so.
If one accepts the first four premises above, then in comparing alternate possible evolutionary explanations the lack of parsimony of the anticipative functions of a cosmic subject could perhaps be weighed against the purported implausibility of evolution having occurred solely through random variation and natural selection. One could argue at length from a philosophical perspective as to which explanation is more plausible or parsimonious. More progress if of course likely to be made by actual testing competing hypotheses.
So how specifically might an anticipative evolutionary drive toward differentiation work and how could it be tested?
Two possible mechanisms are saltation or adaptive mutation. In relation to saltation, the cosmic subject might anticipate that certain major changes in genetic structure could result in the synthesis of proteins which enable the formation of more differentiated organismic forms. Natural selection would then do the work of selecting those forms which are suited to the environment into which they emerge. In relation to adaptive mutation, perhaps the cosmic subject anticipates that certain mutations could lead to new structures that will overcome environmental obstacles an organism faces and thus enhance its potential for differentiation. The latter hypothesis is probably less parsimonious than saltation because it requires attunement of genetic changes to environmental influences. But on the other hand, it is probably more amenable to actual testing (it is difficult to see how one could test for 'hopeful monsters').
To show that adaptive mutation was a result of an anticipative evolutionary drive it would be first necessary to eliminate other possible causes. These could be Darwinian (such as selection acting on a generalised increase in mutation rate in response to environmental stress), or some as yet undiscovered Lamarkian mechanism that provides relevant phenotype to genome feedback.
If such physical explanations had been eliminated then perhaps it could be said there was some support for the anticipative drive hypothesis. The next question would then be what is the actual mechanism by which the anticipative drive effects evolutionary change. That is, how are mutations 'directed' without violating natural law. I think there are two options here. Firstly, the directed mutations could be effected through exploiting indeterminacy at the quantum level. Secondly, one could take a different metaphysical view of the character of physical law, adopting the perspective of Alfred North Whitehead that laws are the 'habits' of nature which on rare occasions may be broken (such a view is also more in keeping with the organic nature of a cosmic subject).
It could be objected here that explaining directed mutation on the basis of quantum events or temporary alterations in nature's habits does not suffice as an explanation at all, because it does not explain the actual mechanism of how the cosmic drive 'causes' the copying errors that lead to the required mutations in nucleotide sequences . But bearing in mind that under the model proposed here the observed physical world is the external aspect of a cosmos with an intrinsic inner subjective dynamic, it may be the case that to ask this question is like asking why fundamental laws and properties are the way they are, and that no further physical explanation can be given.
So it seem to me the scientific investigation of ID as described here would work on a fundamentally negative heuristic - other possibilities are eliminated and we are left with nonrandom directed mutation without a more fundamental physical cause which can be pointed to. In this regard, explanation of direct mechanisms of biological changes, evolution and development are always going to yield a more productive science than that which operates on a negative heuristic of eliminating other possible causes.
Nevertheless, although ID may never be a productive research program in terms of helping us to learn more specifically about how the natural world works this is not to say it may not, after all other physical explanations have been exhausted, be shown to be the best explanation of some evolutionary changes. Of course, even then some might say that deferring to an as yet undiscovered explanation by normal physical means is preferable to postulating an ID mechanism which includes unobservable features. Here we are in the borderlands where philosophy of science meets metaphysics, the issue being whether methodological naturalism needs to be modified to incorporate inferences derived from the natural phenomena of subjective experience.
In light of the above, I think that under a panexperientialist framework some form of minimalist ID could be part of a plausible and parsimonious possible explanation of evolution. Whether such an explanation could ever fall within the realm of science is more problematic. Ultimately, accommodating ID within a scientific framework may require an enlarged conception of what science is (just as David Chalmers has proposed may be necessary for a theory of consciousness ).
In relation to whether such an enlarged conception of science is necessary at the present time, I think the answer is no. There is still so much to learn about life in conventional fields such as molecular biology, genetics and evolutionary developmental biology that it would seem premature to resort to hypotheses concerning a cosmic evolutionary drive. So perhaps the most can be said at the moment is that a panexperientialist form of ID is a plausible hypothetical possibility which is not yet ripe for testing, and may never be.