Consciousness Explained - Synopsis

Synopsis

The book puts forward a "multiple drafts" model of consciousness, suggesting that there is no single central place (a "Cartesian Theater") where conscious experience occurs; instead there are "various events of content-fixation occurring in various places at various times in the brain". The brain consists of a "bundle of semi-independent agencies"; when "content-fixation" takes place in one of these, its effects may propagate so that it leads to the utterance of one of the sentences that make up the story in which the central character is one's "self". Dennett's view of consciousness is that it is the apparently serial account for the brain's underlying parallelism.

One of the book's more controversial claims is that qualia do not (and cannot) exist. Dennett's main argument is that the various properties attributed to qualia by philosophers—qualia are supposed to be incorrigible, ineffable, private, directly accessible and so on—are incompatible, so the notion of qualia is incoherent. The non-existence of qualia would mean that there is no hard problem of consciousness, and "philosophical zombies", which are supposed to act like a human in every way while somehow lacking qualia, cannot exist. So, as Dennett wryly notes, he is committed to the belief that we are all zombies—adding that his remark is very much open to misinterpretation.

Dennett claims that our brains hold only a few salient details about the world, and that this is the only reason we are able to function at all. Thus, we don't store elaborate pictures in short-term memory, as this is not necessary and would consume valuable computing power. Rather, we log what has changed and assume the rest has stayed the same, with the result that we miss some details, as demonstrated in various experiments and illusions, some of which Dennett outlines. Research subsequent to Dennett's book indicates that some of his postulations were more conservative than expected. A year after Consciousness Explained was published, Dennett noted "I wish in retrospect that I'd been more daring, since the effects are stronger than I claimed". And since then examples continue to accumulate of the illusory nature of our visual world.

A key philosophical method is heterophenomenology, in which the verbal or written reports of subjects are treated as akin to a theorist's fiction—the subject's report is not questioned, but it is not assumed to be an incorrigible report about that subject's inner state. This approach allows the reports of the subject to be a datum in psychological research, thus circumventing the limits of classical behaviorism.

Also Dennett says that only a theory that explained conscious events in terms of unconscious events could explain consciousness at all: «To explain is to explain away».