Consciousness Explained
Encyclopedia
Consciousness Explained is a 1991 book
by the American
philosopher Daniel Dennett
which offers an account of how consciousness
arises from interaction of physical and cognitive processes in the brain
.
" 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 zombie
s", 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».
and Thomas Nagel
, argue that Dennett's argument misses the point of the inquiry by merely re-defining consciousness as an external property and ignoring the subjective aspect completely. This has led detractors to nickname the book Consciousness Ignored and Consciousness Explained Away. Dennett and his supporters, however, respond that the aforementioned "subjective aspect" as commonly used is non-existent and unscientific, and that his "re-definition" is the only coherent description of consciousness.
However, John Searle
argues that Dennett, who insists that discussing subjectivity is nonsense because it is unscientific and science presupposes objectivity, is making a category error. Searle argues that the goal of science is to establish and validate statements which are epistemically objective, (i.e., whose truth can be discovered and evaluated by any interested party), but are not necessarily ontologically objective. Searle calls any value judgment epistemically subjective. Thus, "McKinley is prettier than Everest" is epistemically subjective, whereas "McKinley is higher than Everest" is epistemically objective. In other words, the latter statement is evaluable (in fact, falsifiable) by an understood ('background') criterion for mountain height, like 'the summit is so many meters above sea level'. No such criteria exist for prettiness. Searle says that in Dennett's view, there is no consciousness in addition to the computational features, because that is all that consciousness amounts to for him: mere effects of a von Neumann(esque) virtual machine implemented in a parallel architecture and therefore implies that conscious states are illusory, but Searle points out: "where consciousness is concerned, the existence of the appearance is the reality."
Book
A book is a set or collection of written, printed, illustrated, or blank sheets, made of hot lava, paper, parchment, or other materials, usually fastened together to hinge at one side. A single sheet within a book is called a leaf or leaflet, and each side of a leaf is called a page...
by the American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
philosopher Daniel Dennett
Daniel Dennett
Daniel Clement Dennett is an American philosopher, writer and cognitive scientist whose research centers on the philosophy of mind, philosophy of science and philosophy of biology, particularly as those fields relate to evolutionary biology and cognitive science. He is currently the Co-director of...
which offers an account of how consciousness
Consciousness
Consciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind...
arises from interaction of physical and cognitive processes in the brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
.
Synopsis
The book puts forward a "multiple draftsMultiple Drafts Model
Daniel Dennett's multiple drafts model of consciousness is a physicalist theory of consciousness based upon cognitivism, which views the mind in terms of information processing. The theory is described in depth in his book, Consciousness Explained, published in 1991...
" model of consciousness, suggesting that there is no single central place (a "Cartesian Theater
Cartesian theater
The Cartesian theater is a derisive term coined by philosopher Daniel Dennett to pointedly refer to a defining aspect of what he calls Cartesian materialism, which he considers to be the often unacknowledged remnants of Cartesian dualism in modern materialistic theories of the mind.Descartes...
") 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
Parallel computing
Parallel computing is a form of computation in which many calculations are carried out simultaneously, operating on the principle that large problems can often be divided into smaller ones, which are then solved concurrently . There are several different forms of parallel computing: bit-level,...
.
One of the book's more controversial claims is that qualia
Qualia
Qualia , singular "quale" , from a Latin word meaning for "what sort" or "what kind," is a term used in philosophy to refer to subjective conscious experiences as 'raw feels'. Examples of qualia are the pain of a headache, the taste of wine, the experience of taking a recreational drug, or the...
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
Hard problem of consciousness
The hard problem of consciousness is the problem of explaining how and why we have qualitative phenomenal experiences. David Chalmers contrasts this with the "easy problems" of explaining the ability to discriminate, integrate information, report mental states, focus attention, etc...
, and "philosophical zombie
Philosophical zombie
A philosophical zombie or p-zombie in the philosophy of mind and perception is a hypothetical being that is indistinguishable from a normal human being except in that it lacks conscious experience, qualia, or sentience...
s", 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
Heterophenomenology
Heterophenomenology is a term coined by Daniel Dennett to describe an explicitly third-person, scientific approach to the study of consciousness and other mental phenomena...
, 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
Behaviorism
Behaviorism , also called the learning perspective , is a philosophy of psychology based on the proposition that all things that organisms do—including acting, thinking, and feeling—can and should be regarded as behaviors, and that psychological disorders are best treated by altering behavior...
.
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».
Reactions
Critics of Dennett's approach, such as David ChalmersDavid Chalmers
David John Chalmers is an Australian philosopher specializing in the area of philosophy of mind and philosophy of language, whose recent work concerns verbal disputes. He is Professor of Philosophy and Director of the Centre for Consciousness at the Australian National University...
and Thomas Nagel
Thomas Nagel
Thomas Nagel is an American philosopher, currently University Professor of Philosophy and Law at New York University, where he has taught since 1980. His main areas of philosophical interest are philosophy of mind, political philosophy and ethics...
, argue that Dennett's argument misses the point of the inquiry by merely re-defining consciousness as an external property and ignoring the subjective aspect completely. This has led detractors to nickname the book Consciousness Ignored and Consciousness Explained Away. Dennett and his supporters, however, respond that the aforementioned "subjective aspect" as commonly used is non-existent and unscientific, and that his "re-definition" is the only coherent description of consciousness.
However, John Searle
John Searle
John Rogers Searle is an American philosopher and currently the Slusser Professor of Philosophy at the University of California, Berkeley.-Biography:...
argues that Dennett, who insists that discussing subjectivity is nonsense because it is unscientific and science presupposes objectivity, is making a category error. Searle argues that the goal of science is to establish and validate statements which are epistemically objective, (i.e., whose truth can be discovered and evaluated by any interested party), but are not necessarily ontologically objective. Searle calls any value judgment epistemically subjective. Thus, "McKinley is prettier than Everest" is epistemically subjective, whereas "McKinley is higher than Everest" is epistemically objective. In other words, the latter statement is evaluable (in fact, falsifiable) by an understood ('background') criterion for mountain height, like 'the summit is so many meters above sea level'. No such criteria exist for prettiness. Searle says that in Dennett's view, there is no consciousness in addition to the computational features, because that is all that consciousness amounts to for him: mere effects of a von Neumann(esque) virtual machine implemented in a parallel architecture and therefore implies that conscious states are illusory, but Searle points out: "where consciousness is concerned, the existence of the appearance is the reality."
External links
- Dennett, Daniel (1988). Quining Qualia.
- Lormand, E. Qualia! (Now Showing at a Theater near You)
- de Leon, D. The Qualities of Qualia