I’ve been reading Daniel Dennett’s latest book, From Bacteria to Bach and Back: The Evolution of Minds. At the start of the book, Dennett acknowledges that some of his ideas about the mind — in particular, that consciousness is an illusion — are disturbing. He seeks to disarm what he calls a “bristling” response to these threatening ideas. A bristling response, he suggests, is a conditioned response rooted in evolution that produces cognitive distortions. He implies that we should recognize and defuse the bristling response so that we can calmly and rationally evaluate his ideas.
There’s no doubt that immediate emotional reactions such as “bristling” in response to threats are rooted in our evolutionary history. There’s also no doubt that Dennett’s strategy of pointing out this response among readers who feel threatened by the notion that human consciousness is an illusion reflects a powerful rhetorical strategy. But Dennett’s suggestion that a person interested in the truth ought to recognize this response and set it aside makes no sense within the framework of his overarching claims.
“Bristling” is pervasive in nature because it works. Creatures in nature face real threats every day. A response that puts an organism on high alert and that deters the threat helps the organism survive. Far from always representing a cognitive distortion, in nature, bristling often is a truthful, adaptive response to real threats.
The notion that consciousness is an illusion — including, for Dennett, all of our sense of will, intentionality, and moral reasoning — seems like a real threat to human existence. If everyone truly believed and acted on the belief that there is no truth content to consciousness nothing would prevent power and violence from having the final say. Basic structures of law and society might fall away. Bristling here seems like an appropriate response.
But Dennett seems to imply that “bristling” presents cognitive distortions because the response is overdetermined to real threats. That is certainly correct. This overdetermination itself likely is adaptive. Let’s say, for example, that for every twenty “knee-jerk” reactions you have, only one of them responds to a danger of serious injury to your knee. It seems like you’ve expended wasted energy on nineteen useless knee-jerks. But the injury to your knee on that one occasion would have been serious, meaning that the injury would have cost you as much or more, perhaps far more, than the energy you spent on the nineteen “false positive” knee-jerks. On balance, the overdetermination of knee-jerks was relatively efficient because the abundance of caution avoided a serious injury.
No doubt, then, that “bristling” behavior is overdetermined to threats. The next step in Dennett’s rhetorical move is a suggestion that we sometimes need to exercise a higher level of control over our immediate threat reaction in order to assess the situation rationally. This kind of rational control allows us to calibrate our knee-jerks and move to a higher level of efficiency. If we can recognize and avoid the bristling response, we can use our calm, scientific rationality to acknowledge that, in fact, consciousness is an illusion. Further, if we use that same calm, scientific reasoning, we can show why basic structures of law and society that limit power and violence need not fall away and might even be improved.
The obvious problem here is that Dennett’s metaphysical project precludes any such higher level of rational control. Rationality is part of consciousness, so in Dennett’s universe “rationality” cannot exist. You might think you’re exercising rational control over your bristling response, but that, too, is an illusion. Indeed, your “rational” response to your 
bristling reaction is merely another adaptive response. And Dennett’s own rhetorical move of seeking to appease the bristling response through a “friendly” gesture of appealing to reason likewise is yet another merely adaptive response. It’s either “nothing buttery” all the way down, or something else is going on.
As Thomas Nagel suggests in his review of Dennett’s book,
[t]here is no reason to go through such mental contortions in the name of science. . . . To say that there is more to reality than physics can account for is not a piece of mysticism: it is an acknowledgment that we are nowhere near a theory of everything, and that science will have to expand to accommodate facts of a kind fundamentally different from those that physics is designed to explain.
I’d go further than Nagel here and suggest that there are plenty of truths that science simply cannot explain because the natural sciences are not the only, nor even the most basic, way of understanding truth. Understanding truth always, necessarily, begins with metaphysics — and, therefore, with theology — whether acknowledged or not. Dennett assumes a materialist metaphysic with a corresponding (though ultimately incoherent) epistemology and an attendant a-theology, and that, finally, is the rub.
IMG SRC = National Geographic Video; NY Times