Dennett on Consciousness II – And then What Happens?

In Part I I described the introduction of philosopher Dan Dennett to the University of Waterloo for Brain Day, an annual event featuring a panel of speakers with specialty areas in the cognitive sciences. I then began to summarize Prof. Dennett’s talk, introducing the controversial concept of “philosophical zombies” and Dennett’s nonplussed reaction to them. I finished by describing an afterimage effect that seemed to have implications for the way we habitually think about consciousness. In this post, I’ll follow up with said implications and summarize the remainder of the talk – including what Dennett claims to have added to his approach with a small part at the end. Keep in mind that I’m not quite an expert on this stuff, but I’ll do my best to make the relevant points clear and explain why they’re significant.

Gazing at the discoloured American flag for any length of time caused a properly coloured afterimage to appear on the following blank slide. Dennett’s question – where is the red stripe? – seemed to provoke the answer “in our minds!” but he clearly found this answer dissatisfying. It became immediately obvious to me and everyone else in the room that the red stripe was not in the world itself, since it faded away over time and couldn’t be produced without proper preparation. It was equally clear that if the red stripe was only in our minds that it no longer existed strictly as a red stripe. This is my best guess for what Dennett intended to convey with this exercise, because it acted as a good segue to his next example. It also brought to light his immediate dismissal of “objects of consciousness,” since he never entertained the possibility that the red stripe existed in our consciousness (or experience, or qualia). (I’ll come back to correct this assumption if the video footage reveals something that I’ve missed.)

If the red stripe existed in our brains, then it clearly wasn’t as a material or even imaginary red stripe. There were no homunculi seated in our heads assimilating all the sensory stimuli into a coherent image. The red stripe must have existed, then, as a representation, or a pattern of neural activity that was understood to correspond to “red stripe”. Dennett used the example of a DVD to clarify this concept. A DVD is a representation in that it holds information in a format that is different from how it comes to be presented. Unlike a cinema reel, you can’t look or listen very closely at the DVD and recognize tiny versions of its content that only need to be blown up for us to perceive them; the signal is recorded in a different medium. A DVD is not like a representation, however, in the way that we need to somehow convert the representation into a cohesive image in order to comprehend it. To think of the mind in this way is to fall victim to our own metaphors, according to Dennett. This second transduction is completely unnecessary for our mental representations to function correctly.

Here is where Dennett inserted his new addition to the presentation, which was meant to solidify the redundancy of the second transduction. It came in the form of a question – what happens next? Even if we grant the Cartesian Theatre and the second transduction, so that stimuli are appropriately processed and then reconverted into holistic images before a consciousness, what then? The intuitive answer seems to be that the activated cognitive faculties, attention and memory for example, are appropriately affected. Behaviour is adjusted and the cycle continues. This plays into Dennett’s main argument – positing consciousness accomplishes nothing of explanatory value that we haven’t already accounted for with representations.

From here Dennett moved on to lightly address his critics and then illuminate a few interesting functions of representations and the misunderstandings they cause. If rebuttals to Dennett’s take on consciousness can be said to be unnecessarily emotional, it can’t also be said that these outbursts have at all perturbed him. In fact, he seemed quite amused by comments from John Searle and those similarly indisposed to his own views and quoted them directly, at least once being charged as the Devil himself. He recalled a discussion of a famous neuropsychology manuscript – which stated that information was dispersed in the brain before “yielding subjective experience” – where the author was unable to explain the meaning of those words and instead deferred to Dennett to bring forth an answer. Another example of a mixed metaphor was Ned Block’s mental paint, used to create the “conscious image,” which Dennett claimed to have disposed of years earlier as the non-existent “figment”. He also noted the descent of some of his fellow investigators into pansychism, the position that consciousness is a fundamental property of the universe that is inherent to some extent in all matter – asking facetiously about the discernable difference between a “little-bit-conscious” photon and a non-conscious photon.

In an elaboration of how representations do the work that consciousness is proposed to do, Dr. Dennett used a few, perhaps counterintuitive, examples. The first was a long distance impression of a Belotto painting (seen above - forgive the resizing!), which from a distance makes it seem like very detailed people are painted on a faraway bridge. Upon closer inspection the people turn out to be merely inkblots, illustrating the role that context and expectation have on our perceptions. Another example, this one tying evolution into the picture more significantly, had to do with the perception of the cuteness of babies. Dennett reversed the common notion that we find babies cute because we love them with the proposition that we love them because we find them cute – in other words, an evolved tendency to respond favourably to particular kinds of human faces was an effective way of ensuring that infants were well taken care of. In a similar example, the unfortunate Ned Block reported some blurry slides through the course of a presentation, prompting Dennett to ask him whether the slides were blurry in the world or whether the blurriness was internal to Ned. Of course the latter turned out to be the more correct explanation (clearly a problem with Ned's eyes, since the blurriness wasn’t reported by anyone else!)

All these examples were designed to demonstrate that the conscious image that often gets the privileged authoritative position when we choose to examine reality is not only frequently mistaken, but unaware of the mechanisms of its own functioning. “We do not have privileged access to our own machinery,” said Dennett, adding that “our explanations require explanations”. Invoking the manifest vs. scientific image vocabulary of Wilfrid Sellars, Dennett again emphasized the relationship between how we perceive and feel about the world, and the evolutionary tendencies we’ve evolved to respond effectively to environmental stimuli. Like Hume pointed out many years ago, we're psychologically predisposed to misinterpret inner reactions as an outer causes (think of the classic billiard ball example), and our mistaken beliefs can create profound convictions about things that aren't really there. Finally, Dennett's talk closed with a few brief inquiries concerning how technology shapes our expectations and thus our perceptions, creating what he called “expectations about expectations”.

Like any Dennett lecture I’ve seen, the talk overall was light-hearted and oftentimes goofy on the surface, while still maintaining an air of underlying seriousness. He speaks with a deep familiarity of the relevant issues and it’s tempting to take the word of the obvious expert when he declares certain concepts as dualism or pansychism to be nonsense and explanatorily inert. His voice was deep and his delivery, while a little choppy, was aided by PowerPoint text and punctuated by practiced emphasis on certain sentences. Overall I was very happy to have attended and even got the man himself to sign my copy of Intuition Pumps before he went on his way.

All that is not to say I don’t have any criticisms of Dennett’s approach. Despite the reasonableness of his presentation, I still find it incredibly difficult to feel like he isn’t leaving something out. Why couldn’t our brains accomplish the same functions that they do without producing such a convincing and appreciable image? This is a characteristic criticism and one that he urged us to ignore, but it lingered so palpably in the room afterwards that I can’t believe more questions about it weren’t asked. Perhaps the most revealing evidence of this came from the following exchange with a questioner, who seemed to laboriously express the same confusion. After his question (which I don’t quite recall), Dennett responded by asking him how we would find out if a computer program designed to complete a cognitive task analogous to one of our own would then have an identical accompanying experience. The questioner replied immediately with “you can’t,” prompting Dennett to repeat the argument for humans. He certainly doesn’t have the common intuition on his side, but he knows it and comes out prepared to be received with skepticism, and even hostility.

I hope these last two posts were clear enough to present a meaningful summary of a presentation I was lucky to attend. I’ll continue to relate new things I read in the philosophy of mind to them in an attempt to create a productive internal dialogue about these stimulating and contentious problems.