Saturday, March 25, 2006

Pacific APA Highlights Continued

Picking up where I left off in my last post ...

On Thursday evening I sat through an interesting exchange between two process theists (Donald Viney and Randall Auxier), an open theist (David Basinger), and C. Steven Evans, well-known Kierkegaard scholar (I'm not sure where Evans stands vis-a-vis open theism. He's definitely not a theological determinist, however.). Anyway, the two process theists led off with characterizations of process theism from a broadly Hartshornian perspective. Basinger and Evans then gave commentaries, followed by Q&A. One of the things that struck me was that process theism is not as monolithic a movement as I has supposed. Apparently, Hartshornian process theists like Viney and Auxier (especially Auxier) have little sympathy for the sort of Whiteheadian process theism practiced by John Cobb, Jr. and David Ray Griffin. I'm not too clear on the differences, except for the fact that Hartshorne's views seem to be a bit closer to 'classical' theism. Both Viney and Auxier see themselves as Christians and see their process theism as Biblical theism. Auxier even made clear that he wants to affirm creation ex nihilo, although he strenuously reputed the idea of "miracles" as resting on a mistaken conception of God's relation to the world.

Both Basinger and Evans made a similar point in their comments. They both argued that it was wrong to polarize the debate between 'classical' theism and process theism as one between theological determinism and process theism. Both stressed that there was a lot of room in between, including several different versions of what Basinger calls 'free-will theism'. The latter term is his general rubric for any form of theism that affirms libertarian free-will and God's ability to unilaterally act in the world to bring about his intentions. This includes Molinism, simple foreknowledge, and open theism. Both Basinger and Evans also remarked that they were encouraged to see that both process theists and many 'classical' theists are each moving closer together in their respective positions.

On to Friday. I'll be brief here for lack of time. I went to two 3-hour epistemology discussions. The first was a author-meets-critics discussion on Jason Stanley's recent book Knowledge and Practical Interests. Criticisms were given by Stephen Shiffer (NYU) and Gilbert Harman (Princeton), followed by a response from Jason Stanley (Rutgers), and then Q&A. It was quite a lively interaction and Stanley was pressed quite hard from several different directions, but seemed to hold his own. I'll save my own thoughts, however, until I've read his book (probably within the next couple months).

The second epistemology colloquium was very interesting, featuring short presentations of six different papers that are all contributions to a forthcoming book, New Waves in Epistemology. Discussion topics ranged widely, but I was most impressed by a couple papers in formal epistemology, especially Troy Catterson's "The Semantic Turn in Epistemology: A Critical Examination of Hintikka's Logic of Knowledge". Troy's argument ranged over topic like the paradox of the knower, Cantorian arguments against a set of all propositions, and various versions of Jaakko Hintikka's 'epistemic logic'. The upshot is that formal epistemologists badly need a theory of propositions that allows us to speak of a 'proper class' or totality of all truths. Otherwise, paradox and inconsistencies are inevitable.

Well, today's the day on which I read my paper "A Defense of Prior's 'Peircean' Tense Logic". I'll be reading it at 8 pm for the Philosophy of Time Society. I'll post a recap of how that goes later. Right now, I'm going to round me up some grub.

Friday, March 24, 2006

Preliminary Report from the Pacific APA

Well, it's Friday morning here in Portland, Oregon, where this year's Pacific Division meeting of the American Philosophical Association is being held.

On Thursday morning, I went to an interesting session on the philosophy of time. The first paper, by well-known B-theorist Nathan Oaklander, was entitled "Is the Future Open?" As one would expect for a B-theorist, Oaklander's answer is 'no' (B-theorists think that temporal becoming is merely apparent, not real - hence what we think of as the 'future' is always already there.). But I found a couple things interesting about his paper. First, he distinguished between three different senses in which the future might be thought of as 'open' - "openness of time" (i.e., do future events really exist?), "openness of freedom" (i.e., are there future contingents?), and "openness of truth" (i.e., can the truth values of propositions about the future change?). This parallels the threefold distinction that my coauthors and I draw in this forthcoming paper, section 1. Unfortunately, he seemed to think that all three types of openness either stand or fall together, which is incorrect.

Second, Oaklander's target in this paper was the 'growning universe' model as represented by C.D. Broad (in one of his stages) and Michael Tooley. After presenting some general criticisms of that position - which affirms that past and present events exist, but future events do not - he turned to consider whether meeting the challenge of logical fatalism requires an open future. He says, no, of course, but the interesting thing was that his answer appealed to the 'Ockhamist' tense logical view that the present truth of a proposition about a future time depends solely on what actually happens at that time, and not on anything that obtains now. (For an explanation of 'Ockhamist' tense logic and its 'Peircean' rival, see here.)

The next paper was by Mark Hinchliff and was entitled "The Mutable Future". Hinchliff is an A-theorist (he thinks that temporal becoming is real, not merely apparent) and a presentist (he thinks that only present events and states exists). He argued that what is true about the future can change and offered several examples to support his point. The one that received the most discussion concerned the incident from the recent Winter Olympics in which at one point it looked clear that Lindsey Jacobellis was 'going to' win the women's snowboardcross event, and then, after a silly show-off stunt that caused her to fall was 'not going to' win.

After discussing arguments Plantinga and J.J.C. Smart to the effect that the future cannot be changed, "not even by God" (as Plantinga puts it for emphasis), Hinchliff drew upon Peter Geach's work in Providence and Evil (an out-of-print book I'd like to get) to argue for a rejection of 'Ockhamist' tense logic and of the view that future time can be adequately represented by a single, non-diverging line. So far I'm in full agreement, but Hinchliff went on to argue that truths about the future cannot be grounded in present trends and tendencies because such truths are not 'about' present trends and tendencies. The problem is that this leaves him no way to ground truths about the future without falling back into the very 'Ockhamist' tense logic that he's already committed to rejecting. For this reason, he's lead to wonder whether truths about the future can be grounded at all. Furthermore, while Hinchliff is right that propositions about the future are not 'about' present trends and tendencies in the sense that a person making a prediction typically takes himself to be speaking 'about' something future, not something present, this does not imply that the truthmakers of those propositions cannot be identified with present trends and tendencies. Contrary to Hinchliff, the truthmaker for a proposition need not be what that proposition is 'about', where the latter refers to the intentional object that a person expressing the proposition would have in mind. For example, that some dogs exist is made true by Lassie's existence, but one could claim "some dogs exist" without intending to say anything about Lassie.

There was a third paper after Oaklander's and Hinchcliff's by Tomis Kapitan. I won't say much about this. Basically, it amounted to an argument that logical fatalism loses its sting if a compatibilistic view of human freedom and moral responsibility is defensible - nothing particularly controversial there.

After that, I decided to scout around downtown Portland in search of the famous Powell's bookstore and lunch, in that order. I found Powell's after about half-an-hour. It's a hugh store, with a great selection. I found a brand-new book that I had been looking for at about 60% off retail price, and another used book for about half-off retail. Throw in a $5 off coupon I got at the conference, and I was quite happy with myself. Spent another hour after that searching for food - restaurants in downtown Portland seem to be rather scattered - and finally settled for pizza.

Anyway, I think I'll wrap it up now and get back to the conference. I'll post another update tomorrow.

Sunday, March 19, 2006

Love, Hate, Fear, and Indifference

I've been doing some thinking of late about the nature of love. I've already posted some preliminary thoughts about what ideal or perfect love would look like here. In this post I'd like to approach the topic from a different angle, by contrasting love with three of its 'opposites', namely, hate, fear, and indifference.

In brief, here's how I size up the similarities and differences between these four notions:

1. Love, hate, and fear contrast with indifference in that they are all modes of concern with regard to some object. Indifference is simply a lack of concern.

2. Love contrasts with both hate and fear in that love is a positive mode of concern in that it desires and actively pursues the good of its object. Hate and fear, by contrast, are negative modes of concern. Hate desires and, given the chance, actively pursues the harm or destruction of its object. Fear desires and strives to bring about the absence of its object, often by running away.

3. Hate contrasts with fear in that hate is directed toward its object, going on the offensive, so to speak, whereas fear is directed away from its object, going on the defensive, so to speak.

4. Given the above, love, hate, fear, and indifference are contraries to each other. One cannot love something and at the same time and in the same respect either hate, fear, or be indifferent toward it. Mutatis mutandis for hate, fear, and indifference.

Now, here's an interesting question. Which of these - hate, fear, or indifference - is most opposite to love? Or are all equally opposite, but in different respects?

Propositions and States of Affairs - III

My last two posts have been on the topic of the nature and relations of propositions ("props") and states of affairs ("sofas"), respectively. I've been lingering on the topic for two reasons. One is that I've recently become aware of a challenge by Richard Fumerton to my working theory on the topic. Another is that this is one of those topics that as soon as I get it clear in my mind, the fog starts settling in again. I'm hoping that I can meet Fumerton's challenges and clear away my mental fog for good through these posts.

In my last post, I discussed the problem that, on the one hand, props seem to be 'additudinally neutral' since they can serve as objects of various so-called 'propositional attitudes' like "knows that", "believes that", "doubts that", etc. On the other hand, as truth-bearers, props seem to be distinctively assertoric in nature, and thus not additudinally neutral. How do we reconcile this?

Here's a thought that derives from Arthur Prior's tense logic. Prior was a 'presentist', namely, he held that the only time at which anything exists is now - the past is no more, the future is not yet. In conjunction with this, he held that a reference to the present is implicated in all assertions. (For a extended defense of this claim, see Quentin Smith's Language and Time.) Accordingly, in his tense logic he treated the past and future tenses as operators on a core present-tensed prop. Thus,
WILL(p) = It will be the case that p = It will be the case that (it IS the case that p)
WAS(p) = It has been the case that p = It has been the case that (is IS the case that p)
Moreover, the present tense is taken to be basic and irreducible. Thus,
IS(IS(p)) = IS(p) = p
Given that props are fundamentally assertoric, we can parallel this with the notion of truth. Thus,
It is true that p = p
It is true that it is true that p = p
In other words, all propositions by their very nature advance a truth claim, they are assertoric. If this is right, then just like Prior takes the past and future tenses being operators on a core present-tensed prop, so we can take the other propositional attitudes to be operators on a core assertoric prop. Thus,
DOUBTS(S,p) = S doubts that p = S doubts that p is true
So the paradox mentioned above in the second paragraph seems resolvable. We can, it seems, affirm that props are inherently assertoric, not attitidinally neutral, by taking the so-called 'propositional attitudes' to be operators.

So far so good, but there may still be a need for an attitudinally neutral object of thought. After all, we can contemplate both unrealized possibilities ("suppose I inherit a million dollars ...") and impossibilities (e.g., "suppose there is a square-circle ...") without positing either their existence or non-existence. Here's where I think abstract states-of-affairs ("sofas") come in. I can contemplate there being a square-circle, a moment's reflection on which will convince me of its impossibility, at which point I'll be prepared to endorse the prop "It is not the case that there is a square circle." But before the assertion comes the neutral contemplation.

One issue I've got to think more about, however, is the relation between abstract sofas and concrete sofas, between the idea of my inheriting a million dollars and its actually happening. In what sense, if any, are both properly thought of as species of the same genus, namely, sofas?

Friday, March 17, 2006

Propositions and States of Affairs - II

I'm blogging again on this issue of the relation between propositions ("props") and states of affairs ("sofas") because I'm not quite sure I'm got a firm handle on things yet. My understanding of these matters is still somewhat shifting and uncertain. So let's take a fresh look at things from a different angle.

Consider a prop, P. We regularly say things of the form "S asserts / knows / believes / hopes / doubts / fears / etc. that P (is true)." The different verbs (knows, believes, etc.) are commonly said to denote different "attitudes" toward the prop, P. Hence, these are called "propositional attitudes."

Now consider a sofa, X. We regularly say things of the form "S asserts / knows / believes / hopes / doubts / fears / etc. that X (obtains / is actual)." The different verbs (knows, believes, etc.) may be said to denote different "attitudes" toward the sofa, X. Hence, these may be called "statal attitudes."

But is there any real difference between these two modes of discourse? It seems that we can easily translate prop-talk into sofa-talk and vice-versa. So why not just eliminate one of them? It seems gratuitous to posit both props and sofas - where the latter are understood in the Chisholmian (abstract) not the Armstrongian (concrete) sense.

Something like the foregoing line of thought is what motivates Fumerton's argument that
with an ontology of such possibilia there is no need for propositions in addition to states of affairs. We ... could simply identify propositions with states of affairs and analyze truth as "obtaining." (Realism and the Correspondence Theory of Truth, p. 40)
What's key here is the identification of both props and sofas with the common content of the that-clause that is the object of the different "attitudes." And there seems to be something right about this. After all, there clearly is some common content to, say, "S asserts that P" and "S believes that P", and we can only isolate that by abstracting from S's "attitude" toward P. On this account, then, props are attitudinally neutral.

In contrast, I have proposed that props be thought of as intrinsically assertoric in nature. In other words, they are not additudinally neutral. Why think that? Well, my main reasons have to do with truth-conditions and the meaning of assertions. Assertions posit something about the world, and it is this feature that makes them suitable truth-bearers. For example, consider the string of words "Caesar crossed the Rubicon." Does this express something that has a truth-value? Maybe. If the words express the claim that Caesar crossed the Rubicon then they posit something definite, namely, the world's being such that Caesar has crossed the Rubicon, and the claim is true iff the world is as claimed. However, imagine that those words are uttered as part of a query ("Caesar crossed the Rubicon?"). This has no truth-value because it doesn't assert anything to be the case about the world. Similarly, if those words were uttered by an actor in a play who has no idea whether Caesar even existed or whether he is just a fictional invention of the playwrite. Again, the utterance asserts nothing, makes no claim about the world. Hence, it does not have a truth-value.

In general, a given sentence-type is capable of bearing a truth-value only if it is capable of expressing an assertion (i.e., capable of expressing a prop). Furthermore, a given sentence-token bears a truth-value only if it is actually employed to make an assertion (i.e., express a prop).

But if props are fundamentally assertoric, then we need something besides a prop to serve as the common content of the various attitudinal that-clauses. That's where abstract sofas may come in handy, since sofas are attitudinally neutral. Props posit sofas. Sofas posit nothing.

Perhaps, but I'm still not certain I've got this right. More tomorrow...

Thursday, March 16, 2006

Propositions and States of Affairs

I like blogging because it gives me a medium to "test drive" ideas and arguments. One topic that I've been mulling over of late has been the relation between propositions ("props") and states of affairs ("sofas"). My working theory over the past couple years has looked something like this:
  1. Props are assertoric units of meaning that we express by means of "statements", i.e., declarative sentences.
  2. Sofas are conceivably instantiable situations typically expressed by a gerundive noun phrase.
  3. Props posit sofas. For example, the statement "Fluffy the cat is on the mat" expresses the prop Fluffy the cat is on the mat, which posits the sofa Fluffy the cat's being on the mat.
  4. A prop is true if and only if the sofa it posits obtains (is actual). Thus, Fluffy the cat is on the mat is true iff Fluffy the cat's being on the mat obtains, such that Fluffy the cat exists and really is on the mat and not elsewhere.
So far matters seem pretty clear to me, however, issues start arising once we try to figure out how to square 1-4 with the popular view that takes sofas to be actually instantiated situations (a la David Armstrong). On this view of sofas, it is redundant to say that a sofa obtains, since all sofas do so by definition. Those who take this view may charge that I'm introducing needless complications. I need three things in my ontology: props, conceivably instantiable sofas (a type of possibilia), and actually instantiated sofas. Armstrongians seem to need only two: props and sofas. Thus, they will say that a prop is true iff it corresponds to a sofa.

Richard Fumerton expresses this concern in his book Realism and the Correspondence Theory of Truth:
If ... we had in our ontology states of affairs, some of which obtain and some of which do not, then we could let all propositions represent states of affairs - true propositions represent states of affairs that obtain; false propositions represent states of affairs that fail to obtain.... However, with an ontology of such possibilia there is no need for propositions in addition to states of affairs. We would have available a much more straightforward and elegant version of realism. One could simply identify propositions with states of affairs and analyze truth as "obtaining." ... But while [that] view is, perhaps, dialectically attractive, the metaphysical cost is prohibitive. In any event, it is surely desirable to characterize the essence of a correspondence theory in such a way that it is not committed to possibilia. It is desirable because there aren't any such things as states of affairs that do not obtain, and it is desirable because even if there were, it would be a mistake to suppose that the plausibility of the correspondence theory stands or falls on the possibility of defending such a problematic metaphysical claim. (p. 40)
I presume Fumerton's confident that there are no non-obtaining sofas stems from the popular Fregean theory of 'existence'. The Fregean conflates existence-as-actuality with existence-as-class-nonemptiness; hence, to say that there are non-obtaining sofas looks like affirming a contradiction - there exist sofas that do not exist. I've suggested in another post, however, that the Fregean theory might well be wrong. So for my purposes the objection that counts is Fumerton's charge that on my view "one could simply identify propositions with states of affairs and analyze truth as 'obtaining'."

I'm still trying to formulate a clear response to this kind of objection. Here's a rough outline of what I've got so far. Props are assertoric units of meaning; hence, they point to something beyond themselves; they posit something. Sofas, on the other hand, are not assertoric at all. They don't point to anything else. They posit nothing. Hence, only props and not sofas are suited to be truthbearers - they are true iff what they posit obtains. Fumerton's version of the correspondence theory abstracts from the assertoric character of a prop and by doing so deprives him from being able to equate a prop with the meaning of a statement (or assertion).

The confusion I think Fumerton is guilty of (and it is rampant in analytic philosophy) is the same one exemplified by Fregean theories of existence. Peirce calls it 'nominalism', a failure to appreciate 'thirdness as thirdness' by objectifying thought ('thirdness as secondness'). Lonergan calls it 'conceptualism', a conflation of understanding with judgment; a conflation of the meaning of a merely entertained thought (S's being P) with the meaning of an assertion (S is P). Polanyi would call it a failure to appreciate the tacit, personal dimension of all human thought and language. If those thinkers are right, then semantics must not be divorced from pragmatics. Our speech acts don't just color the meaning of our speech, they fundamentally transform it.

Wednesday, March 15, 2006

Some Vacation Highlights

Well, my wife and I are back in Vegas after a six-day California road trip. Here are some of the highlights:

We started out by driving down to the LA area, where we stayed with an old friend from my New York days who now manages a neuroscience lab at UC Irvine. The next day we drove up to Biola Univ. and met with Tom Crisp, who teaches philosophy there. Tom and I have been corresponding via email over the past two months on issues related to presentism and truthmaker theory. We had a good discussion about some of Tom's current research. He's working on the 'cross-time temporal relations' problem for presentism--basically, the problem is that some relations appear to obtain between things at different moments of time, so if the obtaining of a relation entails the obtaining of its relata, then there have to exist things at different times, contrary to presentism. Anyway, Tom's working on a response to that problem and plans to come out with a book on presentism in the next few years.

After that, my wife and I drove north, working our way up the famous Pacific Coast Highway. Along the way we stopped in Solvang, a quaint Danish community; Santa Barbara, where we toured the mission; and Hearst Castle, where we took the overview tour. We stayed a couple days in Monterey, where we toured the Monterey Bay Aquarium and had dinner on Cannery Row. After that, we continued north through Gilroy (the garlic capitol of the world) to Santa Cruz, where we toured the fascinatingly bizarre Winchester Mystery House. From there we worked our way north through San Francisco into the Sonoma area, the heart of wine country. We only had time to stop at a couple of the many area wineries, though. We then headed south to Fresno and were planning to spend the next day exploring Sequoia National Park, but heavy snow had closed the park down, so we came back home instead. All in all, a fun and relaxing trip.

Wednesday, March 08, 2006

Vossler on the Metaphorical Character of Language

From K. Vossler, Positivismus und Idealisms in der Sprachwissenschaft (1904). Quoted by Polanyi in Personal Knowledge (p. 102):
The true artists of speech remain always conscious of the metaphorical character of language. They go on correcting and supplementing one metaphor by another, allowing their words to contradict each other and attending only to the unity and certainty of their thought.
I think this is right, provided one is clear that good artistic writers do not actually contradict themselves. A contradiction that exists at the level of words is merely an apparent contradiction, not a real one. Real contradictions exist at the level of thought and destroy its "unity and certainty".

It can be an enlightening exercise to reflect on the pervasiveness of metaphors in language. Try expunging all metaphors and you'll have a tough time saying much of real significance.

Polanyi on Stage Fright

Michael Polanyi's 1958 book Personal Knowledge gets my vote for most important neglected philosophical masterpiece of the 20th century. It's a wonderful book by a chemist- turned-philosopher of science that is in many ways far more profound than the much more influential work of Karl Popper.

I first read Polanyi's book about 10 years ago and have recently begun re-reading it. One of his central themes is that there is necessarily a "tacit dimension", an inarticulable background, to all human thought. Hence, human thought cannot be fully formalized or articulated.

Polanyi supports this idea in many ways, one of which is a phenomenological analysis of stage fright in terms of "focal" or conscious, attentive awareness and "subsidiary" awareness:
Subsidiary awareness and focal awareness are mutually exclusive. If a pianist shifts his attention from the piece he is playing to the observation of what he is doing with his fingers while playing it, he gets confused and may have to stop. This happens generally if we switch our focal attention to particulars of which we had previously been aware only in their subsidiary role.
The kind of clumsiness which is due to the fact that focal attention is directed to the subsidiary elements of an action is commonly known as self-consciousness. A serious and sometimes incurable form of it is 'stage-fright', which seems to consist in the anxious riveting of one's attention to the next word - or note or gesture - that one has to find or remember. This destroys one's sense of the context which alone can smoothly evoke the proper sequences of words, notes, or gestrues. Stage fright is eliminated and fluency recovered if we succeed in casting our mind forward and let it operate with a clear view to the comprehensive activity in which we are primarily interested. (p. 56)
This seems descriptively accurate to me. When I first read this it occurred to me that my struggles with stuttering are an instance of the same phenomenon as stage fright. Given certain stressers of which I'm often not consciously aware, my focal attention spontaneously shifts to the mechanics of my speech and I start tensing the muscles in the neck in anticipation of certain words. Since air can't flow smoothly through one's vocal chords when the necks muscles are tensed, stuttering results. But whenever my focal awareness stays on the thoughts I'm trying to express and not on the physiological mechanics involved in saying it, I have no trouble.

I encourage readers to test this out. Try doing an activity which you do well, like riding a bike, while consciously focusing on every little detail of that activity: push left foot, adjust handlebars to right, push right foot, etc. You'll quickly see that it's very difficult to operate smoothly. (Warning: Please don't do this while driving on the freeway!)

Saturday, March 04, 2006

Dennett vs. Swinburne on Religion

Here's a nice debate between Daniel Dennett and Richard Swinburne entitled "How Should We Study Religion?" The subtitle implies that Swinburne is a theologian. That's misleading. He's a philosopher of religion and a philosopher of science.

(HT: Victor Reppert)

Wednesday, March 01, 2006

Some Reflections on Stent's Lecture

As noted in my previous post, there was a lecture at UNLV tonight entitled "Intelligent Design: A Unique View of Globalization and Science" by Dr. Gunther Stent. Here are my reflections on the lecture.

The lecture hall was packed--standing room only. Dr. Stent is a recognized expert in molecular genetics, having written an important textbook on the subject. He seemed quite amiable, though because of his age--he's probably in his 70s or 80s--he was hard to hear.

Anyway, I was rather disappointed in the lecture because it hardly engaged with intelligent design at all. Dr. Stent did describe ID as "bizarre", but no explanation or justification was given for that claim. A couple times he lumped it in the same category as "creationism", evincing no clear awareness that the two movements, while overlapping in some respects, are quite distinct.

Most of the talk wandered over a wide array of issues, from comparing C.H. Waddington's and Herbert Spencer's views on the grounding of moral values in Darwinian theory to an extended discussion of Kimura's theory of 'neutral evolution' to speculations on cultural evolution and the possible role that differences in the ratio of brain size to body size might have on rates of "organismal" (or phenotypic as opposed to "genetic" or genotypic) evolution.

His central concern seemed not to be ID at all but contrasting Kimura's neutral evolution with neo-Darwinian natural selectionist orthodoxy. This part of the talk was quite interesting. The basic idea behind neutral evolution is that most of the genetic variation that occurs in a population has little or no direct relation to the "fitness" of an organism. Accordingly, such changes are invisible to natural selection. Nevertheless, if these "neutral" changes proliferate sufficiently throughout a population then they may become "fixed" in the gene pool. Hence, genetic change can occur in species over time even though that change has not been selected for.

According to Dr. Stent, the rate of evolution due to neutral evolution is a factor of (1) the rate of occurrance of a given neutral mutation, and (2) its rate of fixation in a population's gene pool. A given mutation is more likely to occur in a larger population, but fixation is more likely to occur in a smaller population, so (1) and (2) tend to balance each other out. What this means, according to Dr. Stent, is that the rate of neutral evolution is relatively invariant across factors like size of population, rate of reproduction, life-span, and so forth. Instead, the rate of neutral evolution is a more-or-less linear function of time because the other factors balance each other out. Hence, there is a relatively constant "evolutionary-molecular clock".

Dr. Stent seems to think that neutral evolution is the primary source of changes in a population's gene frequencies over time, with natural selection playing only an occassionaly and largely conservation role by weeding out the most unfit. He did suggest that neutral evolution might pose a challenge for ID because random point mutations and genetic drift seem to point away from any sort of telic directedness.

One question I have about this is that if most genetic changes are really selectively neutral, and most of evolution consists in such neutral changes, then it seems to me that it's going to be somewhat hard to account for the occassional rapidity of phenotypic evolution, as in the Cambrian explosion. The problem is that neutral genetic changes have no positive tendency to distribute themselves throughout a population because they are invisible to selection pressure. So in any halfway decent-sized population it could take hundreds or thousands of generations for even one neutral point mutation to become fixed in the gene pool. Given that some creatures have relatively low birth rates, if most of evolution occurs this way, then I'm rather skeptical that there's been anywhere close to enough time for the whole Darwinian tree of life to emerge.

One final remark: Early on in his talk, Dr. Stent admitted quite frankly that the origin or life is utterly "mysterious". He said that no credible naturalistic theory exists to explain how life emerged from non-life. He even went so far as to say that the very quest for a plausible naturalistic origin of life scenario "seems hopeless" and that researchers in that field were quite "discouraged". Later in the talk he referred to Francis Crick's notorious idea of "directed panspermia", basically the notion that life of Earth was engineered by extraterrestrial aliens and then seeded on the Earth. Dr. Stent obviously regarded Crick's suggestion as silly, but by his own admission neither he nor origin-of-life researchers have anything much better to offer. It seems to me that this admission on his part shows that whatever the merits of his views on neutral evolution, ID is still in the game. The most obvious cases of intelligent design are those that stubbornly resist reductive explanation in terms of natural law, chance, or some combination thereof. The origin of life is increasingly looking like just a case.

What is the "Intelligent Design" Movement?

Tonight at UNLV there's going to be lecture entitled "Intelligent Design: A Unique View of Globalization and Science" by Gunther Stent, emeritus professor of cell and molecular biology at UC Berkeley. From the abstract blurb that's going around, I gather that he's no friend of ID but is willing to concede that evolutionary orthodoxy is wrong in some areas. I'll post my thoughts on the lecture afterwards.

For now, I'd like to provide a link to a nice short paper that helps define what the Intelligent Design movement is all about. Critics often try to pigeonhole the movement, either by panning it as an essentially "religious" movement or even more narrowly as merely disguised "creationism". This article shows why those are inaccurate charicatures.

Marcus R. Ross, "Who Believes What? Clearing up Confusion over Intelligent Design and Young-Earth Creationism" (Warning, it's a large file: 5+ MB, .pdf)