Wednesday, September 06, 2006

The Objection from Structure and Dynamics

This is the first in a series of three posts which take a closer look at certain sections of Daniel Stoljar’s book Ignorance and Imagination: The Epistemic Origin of the Problem of Consciousness. In his Chapter 8 he discusses and replies to 2 possible objections to his thesis, and these will be the focus of this post and the next. In another follow-up post I want to discuss his treatment of the Russellian (“neutral monist”) stance.

Backdrop:

To review, Stoljar usefully frames the logical problem of consciousness as follows. We have reason to endorse a triad of inconsistent statements:

1. There are experiential truths.
2. If there are experiential truths, every experiential truth is entailed by some non-experiential truth.
3. If there are experiential truths, NOT every experiential truth is entailed by some non-experiential truth.

Briefly and roughly, experiential truths are events of phenomenal and subjective character for which it is like something to undergo them. Stoljar (rightly in my opinion) takes #1 above to be obvious and does not spend much time on it. We have reason to believe #2 above given the track record of explaining manifest or folk truths in terms of scientific descriptions (which, to-date, all seem to coherently supervene on ground-level truths of physical theory). We might reasonably expect a correct treatment of experience in terms of non-experiential scientific truths to follow in due course. Someone holding to the philosophical position of physicalism (or materialism, to use the older term) accepts #2 and rejects #3. As an aside, I think Stoljar’s choice of using the term “non-experiential” rather than “physical” where possible is helpful, since it is always possible to get distracted in defining “physical” – although there are times where you need to revisit this.

We have reason to believe #3 above due to a number of related arguments, especially those known as the conceivability and knowledge arguments (“CA” and “KA”). For the purposes of my posts, I will presume familiarity with these; for a quick reference on these as well for the objection to Stoljar considered below, see David Chalmer’s paper Consciousness and its Place in Nature (this is also the paper which has his useful taxonomy of positions on the problem – Stoljar’s would be a form of “Type-C” materialism); for a more recent extended treatment of CA from Chalmers, see this paper. Dualists and other critics of physicalism accept #3 and reject #2.

In his book, Stoljar considers and rejects criticisms of CA/KA in the literature with the exception of his own, which he argues is successful. His (disarmingly modest-seeming) stance is an epistemic one, arguing CA/KA fail because we are ignorant of a type of “experience-relevant non-experiential truth”. It is only this ignorance which gives CA and KA their force, and if all the facts were known, we would all reject #3 and accept #2.

In his Chapter 8, Stoljar considers some possible objections and offers replies. He gives a general form of an objection (a master argument) as follows (some paraphrasing): we know we’re ignorant of many things, but we know enough to know that any relevant non-experiential truth is going to be characterized by some Factor X. The problem we have now which leads to the reasonableness of #3 will always re-emerge when we consider these new truths as a result.

Now, let me digress and admit that in similar discussions in the past I might have already given into a temptation to stop and protest: “how can it be that experiential truths can ever be entailed by (or “emerge” from) non-experiential truths? Isn’t the idea of “experience-relevant non-experiential truth incoherent?” Similar sentiments abounded in the Galen Strawson paper I praised and linked to a short while ago (btw, Stoljar has recently posted a response to the Strawson paper). But, in terms of Stoljar’s explicitly epistemic argument, one is not entitled to this response at this point. If the view is correct, then the notion only seems incoherent because of my ignorance. So, we must soldier on and put more flesh on what it is about non-experiential truths (Factor X) which has and will continue to make them incapable of appearing to entail experiential truths.

The Objection from “Structure and Dynamics”

The first candidate for Factor X Stoljar considers, stemming from Chalmers, invokes the idea that physical descriptions invariably characterize phenomena in terms of “structure and dynamics” (sometimes “structure and function” – see the first paper linked to above as well as Chapter 3, section 2 of The Conscious Mind). For any structural or functional explanation of consciousness, we’ll always be able to further ask why such a structure or function is accompanied by experience. Experience will not be entailed by the structural/functional explanation.

Stoljar, reading and interpreting Chalmers, says structure involves either a spatiotemporal relation or the property of playing a certain causal role – in other words what philosophers might also call dispositional or relational properties. Dynamics refers to how the system changes its dispositional or relational properties through time. So, instead of structure and dynamics, one could say “relations and dispositions”. Yet another way to put it is to say that we are referring to extrinsic properties. It is then asserted that these cannot be said to entail intrinsic properties, and experiential truths concern intrinsic properties. In replying to Chalmers, Stoljar refers to structure and dynamics, but says his reply would still hold force if we utilize these other terms.

Stoljar’s first reply to the objection is to say that while we can categorize physical descriptions in term of non-experiential structure and dynamics there also are experiential structure and dynamics. The experiential field has varying degrees of intensity, unity and dispositional qualities (such as a pain getting worse if I move a certain way). So, Stoljar asserts that if one knew everything about structure and dynamics, one would also know about some experiential structure and dynamics. Now, Chalmers might say that knowing about physical structure and dynamics will not help with the distinctively experiential variety of these. But why not? I think Stoljar’s response is effective up to this point.

Chalmers or his stand-in might say next, however, that experiential truths necessarily include another type of truth untouched by structure and dynamics. If so, Stoljar needs to know what this is so as not to beg the original question. A candidate might be intrinsic (non-relational, non-dispositional) properties. Stoljar next replies to this suggestion. He says while it seems that experiences have intrinsic properties (such as the blueness of an expanse of blue sky), it is really the representation of the sky which has the intrinsic property not the experience itself. I thought this was a weak response. It invokes a distinct and controversial argument regarding the representational nature of experience which is orthogonal to the debate at hand.

But Stoljar then offers a second reply to this revised version of the objection (to recapitulate: the idea is that experiential truths sometimes involve intrinsic properties, non-experiential truths never do, and you can’t get derive intrinsic truths from extrinsic ones). He offers examples such as the following: being a husband is an extrinsic (relational) property of Jack Spratt; and being a wife is an extrinsic property of Jack's wife; but being married is an intrinsic property of them as a pair. So the intrinsic fact of the whole did indeed derive from the relational facts of the parts. But, one might respond that this part/whole discussion misses the point when it is argued that it is the extrinsic description of a single thing that will fail to entail the intrinsic nature of that same thing. But, Stoljar seems comfortable to leave things here, thinking one can always assert a relational parts->intrinsic whole for any complex object, and since our starting point is the experience of a complex human individual, this reply has some force. The objector has just one defense left: he could assert that the world has an intrinsic nature at its most basic indivisible level. At this point, the dialectic stops, since the idea that all physical reality has an intrinsic nature relates to the Russellian view that Stoljar treats separately (as will I).

Conclusion

I think Stoljar’s reply to the objection from structure and dynamics is successful up to a point. He pushes the objector toward arguing for an intrinsic nature at the basic level of the world, rather than for a composite individual such as a human per se.


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