Author | Daniel C. Dennett |
---|---|
Country | United States |
Language | English |
Subject | Consciousness |
Publisher | Little, Brown and Co. |
Publication date | 1991 |
Media type | Print (hardcover and paperback) |
Pages | 511 |
ISBN | 0-316-18065-3 |
OCLC | 23648691 |
126 20 | |
LC Class | B105.C477 D45 1991 |
Preceded by | The Intentional Stance |
Followed by | Darwin's Dangerous Idea |
Consciousness Explained is a 1991 book by the American philosopher Daniel Dennett, in which the author offers an account of how consciousness arises from interaction of physical and cognitive processes in the brain. Dennett describes consciousness as an account of the various calculations occurring in the brain at close to the same time. He compares consciousness to an academic paper that is being developed or edited in the hands of multiple people at one time, the "multiple drafts" theory of consciousness. In this analogy, "the paper" exists even though there is no single, unified paper. When people report on their inner experiences, Dennett considers their reports to be more like theorizing than like describing. These reports may be informative, he says, but a psychologist is not to take them at face value. Dennett describes several phenomena that show that perception is more limited and less reliable than we perceive it to be.
Dennett's views set out in Consciousness Explained put him at odds with thinkers who say that consciousness can be described only with reference to "qualia," i.e., the raw content of experience. Critics of the book have said that Dennett is denying the existence of subjective conscious states, while giving the appearance of giving a scientific explanation of them. [1]
Dennett 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". [2] The brain consists of a "bundle of semi-independent agencies"; [3] 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 process in which multiple calculations are happening at once (that is, parallelism ).
One of Dennett's more controversial claims[ according to whom? ] is that qualia do not (and cannot) exist as qualia are described to be. 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 philosophical zombies (if you define the term "philosophical zombie" as functionally identical to a human being without any additional non-material aspects)—adding that his remark is very much open to misinterpretation. [4]
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 do not 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. [5] [6] 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". Since then, examples continue to accumulate of the illusory nature of our visual world. [7]
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.
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".[ page needed ]
The New York Times designated Consciousness Explained as one of the ten best books of the year. [8] In New York Times Book Review, George Johnson called it "nothing short of brilliant". [8]
Critics of Dennett's approach argue that Dennett fails to engage with the problem of consciousness by equivocating subjective experience with behaviour or cognition. In his 1996 book The Conscious Mind , philosopher David Chalmers argues that Dennett's position is "a denial" of consciousness, and jokingly wonders if Dennett is a philosophical zombie. [9] Critics believe that the book's title is misleading as it fails to actually explain consciousness. Detractors have provided the alternative titles of Consciousness Ignored and Consciousness Explained Away. [10] [11]
John Searle argues [12] 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 these statements can be about what is ontologically subjective. Searle states that the epistemic objectivity of the scientific method does not preclude the ontological subjectivity of the subject matter. Thus, back pain exists, they are subjective experiences whose existence is not in doubt in medicine. And neurology, as you can see in any neurology textbook, is concerned with understanding them in order to cure them. 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 writes 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. In contrast, Searle asserts that, "where consciousness is concerned, the existence of the appearance is the reality."
Searle wrote further:
To put it as clearly as I can: in his book, Consciousness Explained, Dennett denies the existence of consciousness. He continues to use the word, but he means something different by it. For him, it refers only to third-person phenomena, not to the first-person conscious feelings and experiences we all have. For Dennett there is no difference between us humans and complex zombies who lack any inner feelings, because we are all just complex zombies. ...I regard his view as self-refuting because it denies the existence of the data which a theory of consciousness is supposed to explain...Here is the paradox of this exchange: I am a conscious reviewer consciously answering the objections of an author who gives every indication of being consciously and puzzlingly angry. I do this for a readership that I assume is conscious. How then can I take seriously his claim that consciousness does not really exist? [13]
Dennett and his illusionist supporters, however, respond that the aforementioned "subjective aspect" of conscious minds is nonexistent, an unscientific remnant of commonsense "folk psychology", and that his alleged redefinition is the only coherent description of consciousness. [14] [15]
Neuroscientists such as Gerald Edelman, Antonio Damasio, Vilayanur Ramachandran, Giulio Tononi, Christof Koch and Rodolfo Llinás argue that qualia exist and that the desire to eliminate them is based on an erroneous interpretation on the part of some philosophers regarding what constitutes science. [16] [17] [18] [19] [20] [21] [22] [23] [24] [25]
Consciousness, at its simplest, is awareness of internal and external existence. However, its nature has led to millennia of analyses, explanations and debate by philosophers, theologians, and all of science. Opinions differ about what exactly needs to be studied or even considered consciousness. In some explanations, it is synonymous with the mind, and at other times, an aspect of mind. In the past, it was one's "inner life", the world of introspection, of private thought, imagination, and volition. Today, it often includes any kind of cognition, experience, feeling, or perception. It may be awareness, awareness of awareness, or self-awareness either continuously changing or not. The disparate range of research, notions and speculations raises a curiosity about whether the right questions are being asked.
The Chinese room argument holds that a digital computer executing a program cannot have a "mind", "understanding", or "consciousness", regardless of how intelligently or human-like the program may make the computer behave. Philosopher John Searle presented the argument in his paper "Minds, Brains, and Programs", published in Behavioral and Brain Sciences in 1980. Gottfried Leibniz (1714), Anatoly Dneprov (1961), Lawrence Davis (1974) and Ned Block (1978) presented similar arguments. Searle's version has been widely discussed in the years since. The centerpiece of Searle's argument is a thought experiment known as the Chinese room.
Daniel Clement Dennett III 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.
Epiphenomenalism is a position on the mind–body problem which holds that subjective mental events are completely dependent for their existence on corresponding physical and biochemical events within the human body, yet themselves have no influence over physical events. The appearance that subjective mental states influence physical events is merely an illusion, consciousness being a by-product of physical states of the world. For instance, fear seems to make the heart beat faster, but according to epiphenomenalism the biochemical secretions of the brain and nervous system —not the experience of fear—is what raises the heartbeat. Because mental events are a kind of overflow that cannot cause anything physical, yet have non-physical properties, epiphenomenalism is viewed as a form of property dualism.
The mind is that which thinks, imagines, remembers, wills, and senses, or is the set of faculties responsible for such phenomena. The mind is also associated with experiencing perception, pleasure and pain, belief, desire, intention, and emotion. The mind can include conscious and non-conscious states as well as sensory and non-sensory experiences.
John Rogers Searle is an American philosopher widely noted for contributions to the philosophy of language, philosophy of mind, and social philosophy. He began teaching at UC Berkeley in 1959, and was Willis S. and Marion Slusser Professor Emeritus of the Philosophy of Mind and Language and Professor of the Graduate School at the University of California, Berkeley, until June 2019, when his status as professor emeritus was revoked because he was found to have violated the university's sexual harassment policies.
David John Chalmers (;) is an Australian philosopher and cognitive scientist specializing in the areas of philosophy of mind and philosophy of language. He is a professor of philosophy and neural science at New York University, as well as co-director of NYU's Center for Mind, Brain and Consciousness. In 2006, he was elected a Fellow of the Australian Academy of the Humanities. In 2013, he was elected a Fellow of the American Academy of Arts & Sciences.
In the philosophy of mind and consciousness, the explanatory gap is the difficulty that physicalist philosophies have in explaining how physical properties give rise to the way things feel subjectively when they are experienced. It is a term introduced by philosopher Joseph Levine. In the 1983 paper in which he first used the term, he used as an example the sentence, "Pain is the firing of C fibers", pointing out that while it might be valid in a physiological sense, it does not help us to understand how pain feels.
Eliminative materialism is a materialist position in the philosophy of mind. It is the idea that the majority of mental states in folk psychology do not exist. Some supporters of eliminativism argue that no coherent neural basis will be found for many everyday psychological concepts such as belief or desire, since they are poorly defined. The argument is that psychological concepts of behavior and experience should be judged by how well they reduce to the biological level. Other versions entail the nonexistence of conscious mental states such as pain and visual perceptions.
In the philosophy of mind, panpsychism is the view that the mind or a mind-like aspect is a fundamental and ubiquitous feature of reality. It is also described as a theory that "the mind is a fundamental feature of the world which exists throughout the universe". It is one of the oldest philosophical theories, and has been ascribed to philosophers including Thales, Plato, Spinoza, Leibniz, William James, Alfred North Whitehead, Bertrand Russell, and Galen Strawson. In the 19th century, panpsychism was the default philosophy of mind in Western thought, but it saw a decline in the mid-20th century with the rise of logical positivism. Recent interest in the hard problem of consciousness and developments in the fields of neuroscience, psychology, and quantum physics have revived interest in panpsychism in the 21st century.
In philosophy of mind, the hard problem of consciousness is to explain why and how humans and other organisms have qualia, phenomenal consciousness, or subjective experiences. It is contrasted with the "easy problems" of explaining why and how physical systems give a (healthy) human being the ability to discriminate, to integrate information, and to perform behavioral functions such as watching, listening, speaking, and so forth. The easy problems are amenable to functional explanation—that is, explanations that are mechanistic or behavioral—since each physical system can be explained purely by reference to the "structure and dynamics" that underpin the phenomenon.
A philosophical zombie is a being in a thought experiment in philosophy of mind that is physically identical to a normal person but does not have conscious experience.
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. As the title states, the book proposes a high-level explanation of consciousness which is consistent with support for the possibility of strong AI.
A Universe of Consciousness: How Matter Becomes Imagination is the title of a 2000 book by biologists Gerald Maurice Edelman and Giulio Tononi; published in UK as Consciousness: How Matter Becomes Imagination. This book, written with Giulio Tononi, is the culmination of a series of works by Gerald Edelman on the workings of the brain which include Neural Darwinism and Bright Air, Brilliant Fire.
In philosophy of mind, Cartesian materialism is the idea that at some place in the brain, there is some set of information that directly corresponds to our conscious experience. Contrary to its name, Cartesian materialism is not a view that was held by or formulated by René Descartes, who subscribed rather to a form of substance dualism.
Philosophy of mind is a branch of philosophy that deals with the nature of the mind and its relation to the body and the external world.
"What Is It Like to Be a Bat?" is a paper by American philosopher Thomas Nagel, first published in The Philosophical Review in October 1974, and later in Nagel's Mortal Questions (1979). The paper presents several difficulties posed by consciousness, including the possible insolubility of the mind–body problem owing to "facts beyond the reach of human concepts", the limits of objectivity and reductionism, the "phenomenological features" of subjective experience, the limits of human imagination, and what it means to be a particular, conscious thing.
In philosophy of mind, qualia are defined as instances of subjective, conscious experience. The term qualia derives from the Latin neuter plural form (qualia) of the Latin adjective quālis meaning "of what sort" or "of what kind" in relation to a specific instance, such as "what it is like to taste a specific apple — this particular apple now".
The Conscious Mind: In Search of a Fundamental Theory was published in 1996, and is the first book written by David Chalmers, an Australian philosopher specialising in philosophy of mind. Although the book has been greatly influential, Chalmers maintains that it is "far from perfect", as most of it was written as part of his PhD dissertation after "studying philosophy for only four years".
The concept of absent qualia is one of two major functionalist objections to the existence of qualia, the other being the inverted spectrum hypothesis. Qualia is a philosophical term used to refer to an individual's subjective experience, that is to say, the way something feels to that individual at that particular moment.