Tuesday, September 27, 2005

Notes on Determinism, Modality and Causality

Below are some thoughts I was trying to develop. Everyone is welcome to point out where I'm getting off-base.

1. If determinism is true, there is no modality: everything is necessary. So, if you take modalities like possibility and contingency to be real, determinism is false.

2. If determinism is true, there is no “real” (non-Humean) causality: everything is connected necessarily and symmetrically; the world is fixed forever. Real causality implies modality: things could have happened differently if causation is assumed to involve real “work”. Like modality, real causality is opposed to determinism.

David Lewis would be able to embrace both modality and determinism by postulating concrete possible worlds (which are causally unconnected to ours) as the vehicle for modality. But he is a Humean about causality. There is no real causation in his system.

The only way to embrace modality and real causation is to reject determinism. This implies that the world includes an intrinsic selection or choosing among possibilities within causal events.

An assertion that only objectively random choosing occurs at this point is ad hoc: it has no particular advantage over asserting that choosing is non-random.

Tuesday, September 20, 2005


A philosopher I like is Hubert Dreyfus, the existentialism and phenomenology scholar. Years ago I got more out of Heidegger by virtue of reading his commentary volume Being-in-the-World. Dreyfus is famous for his criticism of artificial intelligence, especially in the early days when many thought HAL from 2001: A Space Odyssey might soon become a reality! His What Computers Can’t Do from 1972 turned out to be prescient when the early versions of AI (now called “good old-fashioned AI” or GOFAI) started hitting tough obstacles.

I just finished reading Dreyfus’ APA Pacific Division Presidential Address, which was called “Overcoming the Myth of the Mental: How Philosophers Can Profit from the Phenomenology of Everyday Expertise.”

When working on the foundations of knowledge and many other problems, many assume (explicitly or implicitly) that our conceptual thinking facility is the primary dimension of mind. Dreyfus argues that our capacity for detached conceptual thinking rests on top of (is derived from) our non-conceptual embodied engagement with our environment.

The fundamental core of mind is not detached, deliberate, rational, or conceptual; it is our facility for skillful coping with the world. This is a key insight derived from Heidegger and Merleau-Ponty. It is also consistent with an evolutionary perspective on the human mind: after all, this core of skillful coping is what we share with animals and infants. What differentiates the mature human mind is that “we can transform our unthinking non-conceptual engagement, and thereby encounter new, thinkable, structures.” Accounting for this transformation is the research project recommended by Dreyfus.

I have liked this line of argument, and think Dreyfus’ perspective can serve to make the problems of perception and knowledge more tractable, reducing a bit the seemingly huge divide between the mental realm and the rest of the world.

Friday, September 16, 2005

Philadelphia-Area Philosophy

Check out the updated website for the Greater Philadelphia Philosophy Consortium (GPPC). The GPPC is a cooperative effort including the philosophy departments of 13 area universities which sponsors conferences and other events. The 2005-2006 program is up, and also see the link to the regional calendar which includes talks open to the public at the various schools (although you need to confirm these events with the schools as the dates approach.

Friday, September 09, 2005

Fetal Pain

Recently, JAMA published a survey article on Fetal Pain (the abstract is here, the full text requires a fee). The authors reviewed a large number of research papers relevant to the stage of development at which a human fetus feels pain, and, secondarily, on techniques available for direct fetal anesthesia or analgesia in the case of abortion (or therapeutic interventions). Despite the evidence of reflex responses and hormonal responses by the first and second trimester respectively, the authors conclude that analysis of nervous system development indicates fetal perception of pain is unlikely before the third trimester (29 or 30 weeks gestational age). They note that withdrawal reflexes only require peripheral sensory nerves which connect to motor neurons through the spinal column. They assert psychological awareness of pain requires relatively full cortical functioning, which they conclude comes at about 29-30 months.

The article includes a paragraph acknowledging the context: proposed federal legislation which would require physicians to inform women seeking abortions at 20 or more weeks that the fetus feels pain and to offer anesthesia for the fetus (evidently statutes like this have been enacted in Georgia and Arkansas).

Given the highly charged politics of abortion, the article caught a good deal of attention in the press, and a number of critics have disputed the conclusions and/or complained about pro-choice bias given some of the authors’ past affiliations (links here and here: William Saletan’s take on Slate here). I argue below that a different conclusion from the authors' can be reached from the same set of facts.

My interest in this was similar to my angle in my Terri Schiavo and animal consciousness posts: we have a tendency to think of conscious experience as an all or nothing thing, and I’m interested in exploring the evidence that there is more of a continuum of first person experience from minimal to full tilt.

Echoing what I’ve read elsewhere, the authors say the seat of awareness is in the thalamocortical circuitry. While they found no studies of such circuits in fetuses as they relate to pain specifically, they (reasonably) infer conclusions from looking at work on other pathways (like visual and auditory). Now, curiously, the specifics of these studies don’t seem to precisely support the survey article’s conclusion, since they show thalamic projections reaching the cortex at 23-27 weeks. A later part of the paper on electrical activity is invoked to buttress the 29-30 week figure in the conclusion, but this seemed to my amateur eyes less compelling (more indirect) evidence on the question.

Importantly, the authors include a paragraph noting that others have proposed that connection to the cortex could be established indirectly if afferents from the thalamus reach a transient cortical subplate which appears earlier while the layers of the mature cortex are still forming. This happens by 20 to 22 weeks. Given the lack of firm evidence that this connection conveys pain information (as we understand it in fully developed context) the authors don’t give it weight in their conclusion.

The authors do not address the broader question of whether something similar to pain (if more primitive in some sense) exists during development absent any pathway to even a primitive cortical subplate. Is there something in-between the reflex arc and the cortical arc which gives rise to pain-like sensation? At this point we probably have no evidence and can only speculate. But I think it is a reasonable intuition that in different stages of development, intermediate stages of experience may exist.

My problem with this article is not with the factual content, but with the way this is parsed to reach a conclusion. In the absence of compelling evidence that fully developed pain awareness exists prior to 29-30 weeks, the authors conclude it doesn’t. I might place the emphasis differently: while we lack definite confirmation, something similar to our pain awareness might exist at 20-22 weeks, and we just don’t know if a neural response worthy of being compared to pain might exist earlier than that.

I continue to support the legality of abortion; however, I also continue to believe relatively more emphasis should be placed on the procedure being done as early as possible.

Friday, September 02, 2005

Desert Phenomenology

{UPDATE 24 March 2008: Please note the 'Desert Landscape' blog is defunct and the links were broken. A shame}

Uriah Kriegel at Desert Landscapes has had a number of interesting recent posts on phenomenological topics. The most recent discusses Alva Noe and Sean Kelly's take on perceptual constancies, which I discussed in previous posts (here and here). He leans toward Kelly's view as I did.

Thursday, September 01, 2005

Whole Lotta Worlds

I enjoyed reading David Lewis’ On the Plurality of Worlds. Of course, for me it was like entering a theater in the third act: my eclectic self-education has big holes in it which inhibit my comprehension of such a work.

The usefulness of expressing modal concepts in terms of possible worlds seems clear enough (here’s a blog post which outlines this well – hat tip to the latest philosophy carnival). David Lewis argues that the value and utility of possible worlds in modal thinking points to a metaphysical or ontological argument that the full set of possible worlds exists concretely. In the book he defends this thesis.

Most other philosophers would say possible worlds are abstract, like mathematical objects. Even setting aside that the ontological status of mathematical objects is highly controversial topic, Lewis moves from his usual modest tone toward vehemence in criticizing these views as insufficient in supplying the full structure needed for possible worlds; further the question of how the actual world is selected from the set of abstract possibilities is either inadequate or “magical” in competing accounts.

In other words a sufficient proposal for a modal metaphysics either needs to have Lewis’ ontological panoply of concrete worlds, or else we need a fuller account of the ontological status of the abstract world along with a detailed mechanism for selecting the actual world (in Lewis’ scheme, “actual” just means the world we happen to be in, but there is nothing else special about it relative to the other worlds). Note that this means a system with only one actual concrete world and no ‘abstract realm+selection’ endowment is simply an inadequate metaphysics. While Lewis takes this for granted, I think it's interesting that seemingly only a small subset of philosophers would endorse either the Lewisian system or an abstract alternative with full mechanisms for addressing the Lewisian critique. They are presumably content to deal with modality in epistemological and linguistic arenas unburdened by the metaphysical worries.

While Lewis doesn’t explicitly address it much in this book, the other way to parse the metaphysics is in terms of causality. Lewis’ approach enables him to be a Humean about causality. Everything in the world just happens. If we want to talk about what counterfactual situations could have possibly happened to us, say, then we are talking about things that happen to our counterparts in other worlds. If we want to say there is only one concrete world where things happen and these are caused in a way which could have happened differently (they are contingent things), then we need a model of “real” causation that can handle this selection process. These two alternatives exclude the common assumption many seem to share that there is only one world, but a simple billiard ball notion of causation is all we need. In such a world there is no possibility or contingency at all. Again, this would be an inadequate metaphysics.

So, what do I think of Lewis’ proposal? I don’t like the Humean/fatalistic aspect of it. I would like to think a selection process happens rather than think that every possible world exists in an even-handed way, and we just happen to be in one. But at this point this is a preference on my part, not an argument.

What I get out most out of this is what I’ve been emphasizing in this post: Lewis is an obstacle to those who think they can “get away with” a minimalist metaphysics like single-world physicalism. It’s not enough.