Tuesday, March 28, 2006

A further response to Jim Lippard

Naturalists and supernaturalists agree that we do engage in rational inferences. The supernaturalists think we do so using magical non-physical properties; many of them think that our minds are completely independent of our brains, though I think this is a position that is untenable in the face of empirical evidence from neuroscience (evidence which I have yet to see a substance dualist even attempt to address). In the face of arguments about the fact that computers are physical devices which engage in computation and inference, they respond that this is not real computation and inference, but only a derived computation and inference that is fully dependent upon human computation and inference.

I find the use of terms like "supernaturalists" and "magical" to be misleading terms. My argument, first and foremost, is an argument for a dualism of explanations, in which intentional states are permitted as basic explanations. We then can consider what kinds of world-views might allow this kind of explanatory dualism, and these include traditional theism, but also include such options of absolute idealism, the philosophy that Lewis adopted when he became persuaded of the argument from reason.

Lippard seems here to be implicitly using the inadequacy objection, the idea that whatever trouble we might have in accounting for something like intentionality, appealing to nonphysical explanations simply deepens the mystery and makes matters worse. But we have, intuitively a pretty clear understanding of our mental life. It is only when we try to connect it with the non-mental life of the material world that things get difficult. The following passage, from my essay "The Argument from Reason and the Humean Legacy," is germane here:

The Inadequacy Objection gratuitously assumes that matter is what is clearly understandable, and that “mind” is something mysterious, the very existence of which has to be explained in terms of un-mysterious matter. But is this an accurate picture? According to Galen Strawson,
This is the assumption that we have a pretty good understanding of the nature of matter—of matter and space—of the physical in general. It is only relative to this assumption that the existence of consciousness in a material world seems mystifying. For what exactly is puzzling about consciousness, once we put the assumption aside? Suppose you have and experience of redness, or pain, and consider it to be just as such. There doesn’t seem to be any room for anything that could be called failure to understand what it is.
On the other hand, matter is described by modern physics in the most mystifying terms imaginable. The philosopher of science Bas van Fraassen writes, “Do concepts of the soul…baffle you? They pale beside the unimaginable otherness of closed space-times, event horizons, EPR correlations, and bootstrap models.”

Naturalists, by contrast, think that our abilities to engage in rational inference and language have evolved, and that they are both dependent on natural causes and productive in generating additional natural causes of reasoning and action. They are far from perfect--we can identify systematic failures of reasoning that occur (e.g., examples of the sort in Kahneman & Tversky's classic Judgment Under Uncertainty). And our understanding of our own abilities is far from complete--but is growing rapidly.

Of course I never said that our rational faculties were perfect, nor did I say that they were completely independent of matter. Dualists like Taliaferro and Hasker, as well as C. Stephen Evans in a paper for Christian Scholar's Review, freely acknowledge the extensive role of the brain in cognition. In fact, I don't know any dualist that denies it.


Scientific examination of our cognitive capabilities has been extremely productive, while the supernatural thesis has been moribund.

The scientific study of the brain requires only extensive correlations between mental states and brain states, a claim that both naturalists and "supernaturalists" can agree on.


Jim Lippard said...

"But we have, intuitively a pretty clear understanding of our mental life."

Intuitively, it seems that we see the entire visual field before us as a single, clear, coherent picture. But we don't, which can be empirically shown. First, we have a blind spot that our brains fill in based on context. You can perform simple tests on your own to show some of the characteristics of the filling-in process. (There's a chapter in Ramachandran's _Phantoms in the Brain_ which shows how to do this.) Second, our eyes are engaging in saccades to fill in details, and we only actually see sharply in real time what our eyes are focusing on at the moment; the rest is fuzzy, but is kept clear in memory, not in real-time. There's an entertaining lab experiment where a device tracks the focus of your eyes, and maintains a page of text with fixed content wherever the test subject focuses, while constantly changing the rest of the page. The test subject sees a fixed, unchanging page, while everyone else watching sees a buzzing chaos of changes on the screen.

The commonsensical, intuitive view and the scientifically informed view diverge. Substance dualists seem content with the former, with the result that their theories don't accord with the latter.

My point isn't the inadequacy objection, exactly--rather, it's that we *are* gaining adequate explanations based on the physical attributes and components of the brain that explain phenomena like what I just described, while nonphysical explanations offer nothing.

Don Jr. said...

How do eye movements explain reason physicalistically? And dualism doesn't deny the existence of a brain. So how exactly has the "scientifically informed view" diverged from dualism?

Victor Reppert said...

There is a difference between a scientifically informed view of cognition refining and correcting our common-sense view of cognition and that scientific view simply overthrowing it. Telling us that there are no beliefs, which is what eliminativists say a "scientifically informed" view will tell us, is to overthrow our commonsense view. This neuroscientists, who is raising doubts about the external world, is another.


If this is the upshot of cognitive science, then it will undermine itself by denying the extrenal reality of spoons, and brain scanners as well.

Jim Lippard said...

"How do eye movements explain reason physicalistically? And dualism doesn't deny the existence of a brain. So how exactly has the "scientifically informed view" diverged from dualism?"

The point of the example isn't the eye movements, but that, by reflection and experiment, the "obvious" and "intuitively clear understanding of our mental life" can be shown to be mistaken.

Dualism doesn't deny that there is a brain, but it claims that there are important functions on the nonphysical side of the ledger. The more we discover about neurology, the more functions get put on the physical side of the ledger. The scientific data makes substance dualism--at best--like a "God of the gaps" argument. The more we learn, the less possible work there is for any alleged nonphysical to be doing.

I think it was Victor who posted something recently quoting David Chalmers about a resurgence of dualism in philosophy of mind--but what was noteworthy was that all of his examples were property dualists, not substance dualists. Are there any major figures in philosophy of mind who come to grips with the scientific data and still maintain substance dualism? Or are they all people who also reject firmly established facts like those of the evolutionary sciences?

Victor Reppert said...

I don't think you reject established facts to be a substance dualist; at worst you reject Ockham's Razor. Further, if you call something matter but you attribute to it causally relevant properties that are not physical, (and hence reject that causal closure of the physical) you have all the dualism that I am looking for. I never deny that what I call the soul is located in space, for example. It is just subject to different fundamental laws than ordinary matter. So by some definitions I would qualify as a materialist..

Jim Lippard said...


I don't think Hoffman's view is the upshot of cognitive science or is a plausible view. I don't particularly care for eliminativism, either, but I think it's a much more plausible view--while it says that there are no beliefs in the form of sentence-representations in the head, there is still representation, and representations which give rise to utterances of sentences about dispositional mental states.

From my limited study, I see fairly radical revisions to common sense about perception (e.g., visual processing) and memory (e.g., the way recall is a reconstructive process), at the very least.