Monday, January 28, 2008

The Intelligent Design Contention: Part4

Casey Luskin
In this web article Casey Luskin, Intelligent Design apologist, responds with a comprehensive rebuttal of America’s National Academy of Science’s negative assessment of ID. The article exploits the self-criticizing quotes of evolutionary theorists who candidly admit weaknesses and gaps in the theory in relation to a variety of outstanding problems: the inconsistencies in trying to build phylogenetic trees, the poor state of abiogenesis, problems in relating evolution to the fossil record, and the patchy evidence of hominid evolution. For me these problems are not unexpected given the nature of beast – evolution is one of those big historical theories dealing with a complex ontological category. My own gut feeling is that evolutionary theory, given what it is trying achieve, does a good job of achieving it – that of linking a diversity of observations into one theoretical framework. It will, of course, never be so sure footed as say celestial mechanics, or atomic theory, simply because it deals with such epistemologically intractable objects as deep time and, it hardly needs be said, the most complex objects we know of – living things. It is unfair, as does Luskin in his article, to make comparison with the much simpler objects that physics studies. Evolution is certainly not less well founded than some of the other epistemologically tricky things I believe in like, for example, historical narratives, middle of the road socialism, the constitutional monarchy, or theism. I take evolution and evolutionists seriously. It’s one thing to criticize evolution, but it’s quite another to attempt to advance an alternative theory that is as successful.

But I also take Luskin and his fellow ID proponents seriously and especially that key concept of ID, irreducible complexity. In this series of blogs I will be using my blog as a kind of sounding board to help develop my abstract ideas in relation to this key ID notion. In ID theory, if theory it is, the whole edifice of intelligent design stands or falls by the notion of irreducible complexity. Hence it is this concept that I want to focus my efforts on here.

In his article Luskin addresses the NAS treatment of irreducible complexity. He answers the sort of criticism of irreducible complexity that we find in the video of Ken Miller which I posted in my last entry on this subject:

Dembski …. recognizes that Darwinists wrongly characterizes irreducible complexity as focusing on the non-functionality of sub-parts. Conversely, pro-ID biochemist Michael Behe, who popularized the term “irreducible complexity,” properly tests it by assessing the plausibility of the entire functional system to assemble in a step-wise fashion, even if sub-parts can have functions outside of the final system. The “leap” required by going from one functional sub-part to the entire functional system is indicative of the degree of irreducible complexity in a system. Contrary to the NAS’s assertions, Behe never argued that irreducible complexity mandates that sub-parts can have no function outside of the final system.

Luskin also quotes Michael Behe the “Galileo” of ID who explains why the existence of the Type Three Secretory System, as a precursor of the E. Coli flagellum proves little:

At best the Type Three Secretory System represents one possible step in the indirect Darwinian evolution of the bacterial flagellum. But that still wouldn’t constitute a solution to the evolution of the bacterial flagellum. What’s needed is a complete evolutionary path and not merely a possible oasis along the way. To claim otherwise is like saying we can travel by foot from Los Angeles to Tokyo because we’ve discovered the Hawaiian Islands. Evolutionary biology needs to do better than that.

Our ignorance of the structure of morphospace is cutting both ways here: Behe is claiming that absence of evidence of possible evolutionary routes in morphospace is evidence of absence. On the other hand evolutionists claim that absence of evidence of these evolutionary paths is not evidence of absence. Of course, neither party has provided killer evidence either way. So who has the edge here? The claims of ID theorists and evolutionists are, logically speaking, in complementary opposition rather than symmetrical opposition. It is surely an irony that of the two sides ID, in an elementary Popperian sense, is ostensively making the more easily refutable claims: ID is stating a quasi-universal, namely that evolutionary paths to the working structures like the flagellum of E. coli don’t exist – all we need to do is find one route and the proposition is ‘falsified’. Evolutionists, on the hand are making an existential statement; they are claiming that the routes do exist: such statements can’t be falsified, but they can be ‘verified’ by just one case - if they find that one case their claim is ‘proved’. But both sides have their work cut out; the sheer size and complexity of morphospace makes it a little more difficult to investigate than the Pacific! Moreover, the ontological complexities of what is basically a historical subject will no doubt scupper any claims of either absolute falsification or verification and at best only evidence tipping the balance in one direction or the other is likely to be found.

However, having said that the existence of “islands” such as the TTSS do start to weaken the ID case: the ‘irreducible complexity’ of the flagellum structure is thus less irreducible than we were lead to believe; the TTSS sets a precedent that starts to erode blanket claims that evolutionary paths don’t exist. If Behe is so demanding as to require evolutionists to map out a full path, then it is only fair that evolutionists are as equally demanding and require ID theorists to show that such paths don’t exist. So given that neither party can easily provide a suite of evidence that comprehensively proves their case, we have to plump for partial evidence weighing the case in either direction. Thus, in this weaker sense the TTSS is evidence in favor of evolution, whatever Behe says.

Since the ID theorists have come up with no absolute proof that evolutionary routes to their ‘irreducibly complex’ structures don’t exist, they are forced to sit with a passive uneasiness hoping that such paths don’t pop out of the scientific woodwork. There is a marked difference in the strategic positions of the opposing sides: ID theorists are in passive defense, hoping that evolutionary paths through morphospace will not be found. Evolutionist, on the other hand have the initiative – they can imaginatively and proactively search for solutions – and who knows, they may yet come up with the goods. Frankly from a strategic point of view I would rather be an evolutionist.

One final question that Luskin addresses is this: Is ID science? Luskin says, Yes, of course it is! True, the notion of irreducible complexity as a bare idea is an intelligible notion that can be investigated empirically and logically, although as it deals with the structure of that complex beast we call morphospace, scientists have their work cut out. However, it is when ID theorists jump from irreducible complexity to the operation of intelligence, that the waters start to muddy. When we discover an archeological object that looks like an artifact the working assumption is that it is human intelligence has been at work. We can test this assumption in relation to the known traits of human beings. But ID does not identify the source of the artifaction and in spite of using the scientific sounding term ‘Intelligent Design’, that intelligence is a wild card: it is a naked intelligence of unknown powers and motives. This throws into sharp relief such questions as: What is the nature of intelligence? How does intelligence achieve what it does? Why is intelligence needed to create certain structures? It is these sorts of questions I hope to probe and make some progress with in this series of posts.

Monday, January 14, 2008

The Intelligent Design Contention: Part 3

Ken Miller
Here is a video of a lecture from the biologist Ken Miller (see picture) speaking out against Intelligent Design. Miller is a Catholic and evolutionist. I don’t fully agree with all that he says about the nature of science: I don’t think a clear cut distinction can be made between the ‘natural’ and ‘supernatural’, with science only dealing in the former; the ontological and epistemology categories in our world are too blended for us to sharply partition the world in this way. However, the philosophy of science isn’t the issue I wish to pursue here. In this connection I am more interested in Miller’s comments on the ‘science’ of ID. Miller uses his area of expertise in biology to effect when he successfully challenges the ID notion of irreducible complexity, especially in connection with the E. Coli flagellum, the immune system and the blood-clotting cascade. He shows the ID view that parts of these systems are of no use by themselves to be false. He also makes some very notable observations on the tactics being used by the ID community.

Miller makes a particularly compelling point (apparently one of the points that helped carry the Dover trial ruling against ID) when he suggests that the introduction of ID into classrooms under the rubric ‘Teach the Controvesy’ creates a false dichotomy between science and religion; That is, it frames the debate to look as though it is ‘naturalistic’ evolution vs. ‘supernatural’ creation by God with, of course, ID coming in on the side of God against those who, like myself, favour evolution. Ironically, many atheists would agree with this framing. This is typical, typical of so much evangelicalism – lines are drawn in order to define the ‘view of the righteous’ and wo betide you if you find yourself on the wrong side of the line. In this way spiritual duress is applied and this has the effect of pressuring believers to fall into line.

Not that Miller’s own denomination doesn’t have a history of pressuring believers to fall into line. Although I am very uncomfortable with centrally controlled religion, in this case Miller’s denomination is reaping a benefit: If the leadership just happen to take a reasonable view on an issue this can make itself felt all the way down the line (but, of course, the reverse happens as well!). In contrast evangelicalism is highly fragmented, with local fanatics often securing and commanding ignorant and gullible followings.

Friday, January 04, 2008

The Intelligent Design Contention: Part 2

Intelligent Design Examples
The de-facto symbol, rallying emblem, and prototype of the Intelligent Design School is the propulsion flagellum of the Bacteria Escherichia coli. A complex motor like construction delivers the revolutions to the flagellum. The ID case may derive some of its compelling quality from diagrammatic representations of the flagellum drive. These diagrams (see picture) show a structure with rotary components that has at least a superficial resemblance to a piece of human engineering. This resemblance may help elicit the intuitive gut reaction “An inventor must have designed and made it!”. Just looking at representations of the flagellum drive sets the mind up to be more susceptible to the ID contention that this structure of harmonized components must have come together in one grand slam creative act overseen by an Intelligent Designer. Clearly this designer knew all about wheel bearings long before humans were rolling stone monuments of Eygptian kings on logs. Inventors, particularly male inventors, have never been able to get the invention of the wheel out of their heads and when they see a wheel they know there must be a like mind around somewhere.
Other examples of biological engineering used to promote ID are the blood clotting cascade and the immune system (The arguments ‘for and against’ here can be locked onto using Google). These molecular level systems do not just depend on the production of a single protein but consist of a molecular 'industrial process' like production line of inter-dependent proteins that achieves the required result. Remove one protein from this production line and the functionality of the system is severely compromised. Thus, if vital biological systems like blood clotting and the immune system fail to function for want of a single component, then the organism hosting these substructures becomes unstable and dies. In the abstract the ID argument is this: how could all these parts have come together without intelligence? For clearly, ID theorists argue, they must have come together as a whole because removal of any one part leads to failure of function and death. These systems, they claim, cannot be made any simpler; that is, they cannot be reduced – they are ‘irreducibly complex’. The two ‘big name’ Christian theorists associated with the defense of the concept of irreducible complexity are Michael Behe and William Dembski. In some Christian circles they are megastars, Davids fighting courageously against the Goliaths of evolutionary theory.

I recently heard about another ID theorist whilst reading reading Sandwalk, the blog of atheist Larry Moran. Sandwalk reported (critically, of course) on the work of Canadian ID theorist Kirk Durston who is researching proteins, the active chemical ‘bricks’ of living things. To carry out their function the long molecular strands comprising protein molecules must be folded into appropriate shapes. According to Durston there comes a point when incremental changes in the molecular sequence of proteins completely disrupts their folding, thereby making them non-functioning. Durston is claiming that if changes in the molecular structure of proteins go beyond a certain magnitude threshold they cannot do their job. Once again the ID case rests on the difficulty of conceiving how certain biological structures could have come about except as complete up and running systems. The concept of irreducible complexity does not recognize half-measure structures – structures either work on they don’t. Biological solutions, it is claimed, have no sense of nearness or vicinity attached to them – they have to be either bang on target or they are a complete miss.

The ID vs. Darwin debate usually centers round specific organic examples like the prototypes I have given above. There seems to be a reason for this example-by-example treatment. Morphospace is a colossal and hugely complex platonic construction, highly inhomogeneous in its possibilities, and embracing objects of different types and levels – from atomic configurations that make up proteins, through the molecular reactions of protein production lines, to the micro engineering of E. Coli. One could of course, introduce even higher types – e.g. fully blown organisms or an ant’s nest (which is effectively a structure made of many individual organisms). Another tricky facet of morphospace is that environment has a critical bearing on the stability of structures; a structure that is stable in one environment might be unstable in another. Also, a structure may effect or become part of an environment thus giving rise to the non-linear effects of feedback. Moreover, strictly speaking mophospace doesn’t just include biological structures, but just about everything that we can conceive of, and more, that can be made from atomic matter; this even includes human artifacts like a bar of soap, a house, Lego, a jet fighter, a computer, or a Von-Neumann machine. The class of objects covered by morphospace are so varied in typing and level, with so many unknown degrees of freedom, so open ended in functional possibilities that general analytical treatment of this ‘space’ seems to be beyond the wit of man and hence the need to dwell on the specific rather than the general.
But in spite of all this ID theorists are committed to the notion that in critical biological regions morphospace possesses a feature that is a barrier to evolution, or at least in the examples they constant hark back to: they see these example biological structures standing isolated in a kind of design vacuum; that is, they are not surrounded by lower ‘marks’ or similar structures that could be part of an equally stable nexus. Thus, according to ID theory they have no stable neighboring structures that evolutionary gradualism could have passed through en route to the ‘final design’. ID theory therefore swings on the assumed disconnectedness of the regions of structural stability in morphospace. This is the rather brave and quite possibly wrong assumption on which ID theory rests, but it seems that the conceptual intractability of morhpospace, so vast in its ramifying possibilities and typing, makes it difficult for evolutionists to refute this assumption with one-liners. The result is much frustration, annoyance and abrasive dialogue.