The simple truth of the matter is that Dennett is a fanatic: He believes so fiercely in the unique authority and absolutely comprehensive competency of the third-person scientific perspective that he is willing to deny not only the analytic authority, but also the actual existence, of the first-person vantage. At the very least, though, he is an intellectually consistent fanatic, inasmuch as he correctly grasps (as many other physical reductionists do not) that consciousness really is irreconcilable with a coherent metaphysical naturalism. Since, however, the position he champions is inherently ridiculous, the only way that he can argue on its behalf is by relentlessly, and in as many ways as possible, changing the subject whenever the obvious objections are raised. For what it is worth, Dennett often exhibits considerable ingenuity in his evasions — so much ingenuity, in fact, that he sometimes seems to have succeeded in baffling even himself.
David Bentley Hart has criticized Daniel Dennett's naturalist theory of mind on various occasions, arguing that Dennett's approach is reductionist, materialistic, and fails to account for the subjective nature of consciousness. Dennett, on the other hand, has responded to these criticisms in several ways.
Firstly, Dennett has argued that his approach is not reductionist in the sense that he is not reducing subjective experience to something purely objective. Rather, he is trying to provide a naturalistic explanation for subjective experience that is consistent with scientific findings. According to Dennett, subjective experience is a complex phenomenon that arises from the interaction of various processes in the brain, and it is possible to understand these processes without invoking anything supernatural.
Secondly, Dennett has rejected the charge of materialism, stating that he is not claiming that everything is reducible to matter. Instead, he argues that the mind is a complex system that cannot be reduced to any single element, be it matter or something else. In this sense, Dennett's approach is more nuanced than the crude materialism that Hart is criticizing.
Thirdly, Dennett has argued that his approach does not ignore the subjective nature of consciousness. On the contrary, he believes that subjective experience is a crucial aspect of consciousness, and he has proposed several theories to explain it. One such theory is his multiple drafts model, which posits that there is no single "stream of consciousness" but rather multiple competing drafts of experience that are constantly being revised and integrated.
Overall, Dennett would likely respond to Hart's criticisms by arguing that his approach is not as reductionist, materialistic, or dismissive of subjective experience as Hart suggests. Rather, he would maintain that his naturalistic approach to the mind is grounded in empirical evidence and provides a more comprehensive understanding of consciousness than any supernatural explanation could.
When, however, those same methods cease to be regarded as mere useful fictions, conveniently simplifying reality and authorizing only very limited conjectures, and are instead permitted to metastasize into a metaphysical claim about the nature of reality, they can yield nothing but preposterous category errors. At that point, the sheer wanton grandness of the ambitions they prompt renders them impotent.
It may be very helpful, for instance, to investigate specific organic functions found in nature as though they were mere machine functions; but if one forgets the difference between organisms and machines, or ventures even further beyond the frontiers of the verifiable and concludes that nothing but machines really exist, then one has lost the ability properly to see the limits of one’s knowledge.
All of this (and I apologize for so elliptical an overture) is by way of observing that there is no such thing, in the terms acceptable to us today, as a “science of consciousness.” Nor, in fact, could there be....The reason for this is almost banal: Consciousness, uniquely, is not a third-person event reducible to purely objective description, but is first-person in its phenomenal structure all the way down.
There are, of course, cognitive sciences, and our knowledge of the neurological correlations between certain mental states and certain brain states is advancing at—if not an extraordinary—at least a persistent pace. But correlation is not causation; and a correlation between qualitatively irreconcilable phenomena does not even allow us to presume which side, if either, might enjoy causal priority in the relationship.
Consciousness, uniquely, is not a third-person event reducible to purely objective description, but is first-person in its phenomenal structure all the way down. And yet it is an indispensable prejudice of modern method that a verifiable scientific description must be an entirely third-person narrative of structural and causal connections and correspondences.
It is precisely the first-person perspective that must be subdued, and even ideally banished from our final account of any phenomenon, in order for a properly “scientific” account to emerge from observation and experiment and theory. Any remainder of the pure subjective constitutes merely an area of unintelligibility. And this, needless to say, becomes something of an intractable problem when the phenomenon under investigation happens to be subjectivity as such.
The conscious mind cannot be exhaustively accounted for solely in terms of the mechanics of sensory stimulus and neurological response, because neither stimulus nor response is, by itself, a mental phenomenon; neither, as a purely physical reality, possesses conceptual content, intentional meaning, or personal awareness.
To be honest, the incommensurability between physical causation and mental events is so vast that one can confidently assume that no purely physical explanation of their relation will ever succeed
There is so absolute a qualitative abyss between the objective facts of neurophysiology and the subjective experience of being a conscious self that no model of the former, be it ever so sophisticated, can produce an adequate causal narrative of the latter: the two sides of the correlation simply cannot be collapsed into a single observable datum, or connected to one another in a clear causal sequence, and so the precise relation between them cannot be defined, or even isolated as an object of scientific scrutiny.
More to the point, the very notion that consciousness can be conceived as a cumulative quantity, whose smaller units can combine into larger unified aggregates, is also self-evidently absurd.
One neuronal event can cause another as a result of physical necessity, but certainly not as a result of logical necessity; and it is impossible to imagine how the connections among the brain’s neurons could generate the symbolic and conceptual connections that compose an act of consecutive logic, because the brain’s neurons are connected organically and interact physically, not conceptually. [emph added]
The hopelessness of the situation should not be all that difficult to appreciate. For one thing, absolutely central to the mechanistic vision of reality is the principle that material forces are inherently mindless, intrinsically devoid of purpose, and therefore only adventitiously and accidentally directed towards any ends; they can become “purposive” only in a secondary sense, as the result of evolutionary attritions
I may be a physical system in some sense, but I am also an intentional “system” whose mental acts take the forms of semeiotic (symbolic, interpretive) determinations. This means that much of what I do is the consequences of intentions that are teleological in form. As such, they are necessarily invisible to a reductive inventory of the discrete processes composing me as a physical event.
At least, such is the contention of Denis Noble, perhaps the subtlest champion of systems biology or (as he also calls it) “biological relativity.” Perhaps there was a time when one could innocently think in terms of a master ground or center of life, with the DNA molecule as the primordial genetic repository of information (whatever that means)...
He understands, for one thing, that such teleology is an intrinsic rational determination within a complex system, not a factitious purpose extrinsically imposed by some detached designing intelligence. He also understands, however, that there clearly are levels of explanation at which purpose constitutes not just an illusory epiphenomenon of inherently purposeless material processes, but a real causal power. An organ, no matter how stochastic its phylogenic history, exists within an organism because of the purpose it serves
But, unless we want to embrace the plainly magical concept of emergence that I touched on in my first installment in this series, we are still obliged to assume that the formal determinations of organic complexity—or, as we now call it, their “information”—are already present in those causes in at least latent or virtual form, awaiting explication in developed phenotypes and other organic totalities.
Again, irreducible emergence is a logical nonsense; whatever properties appear in an effect, unless imposed adventitiously, are already implicit in its “lower” causes, even if only as a kind of virtual intentionality.
Perhaps mechanistic models never were anything more than artificial constraints, by which discrete processes might be prescinded from a whole that, in itself, has something like the structure of intentional thought.
If, as I say, reason abhors a dualism, all phenomena should ideally be reducible to a single, simpler, more capacious model of reality. So, then, rather than banishing mind from our picture of nature, perhaps we should reconsider the ancient intuition that nature and mind are not alien to one another precisely because nature already possesses a rational structure analogous to thought
The intentionality of mind then is neither a ghostly agency inexplicably haunting a machine, nor an illusion reducible to non-intentional and impersonal forces, but instead the most intense and luminous expression of those formal and teleological determinations that give actuality to all nature.