Searle and Chalmers
SUMMARY AND REVIEWS OF THE LITERATURE ON CONSCIOUSNESS
JOHN SEARLE AND DAVID CHALMERS
reviewed By ANIL MITRA phd, 1999 updated May 2003
REFORMATTED February 2015
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Document status: Thursday, February 05, 2015; no further action needed; may be useful if I write specifically on consciousness and mind.
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OUTLINE
The Reviews 4
John Searle, New York Review of Books, The Mystery of Consciousness, 1997 4
John Searle, The Rediscovery of The Mind, 1992 12
David Chalmers, The Conscious Mind, 1996 22
Copyright and Latest Update 26
Footnotes 26
CONTENTS
The Reviews 3
John Searle, New York Review of Books, The Mystery of Consciousness, 1997 4
Consciousness as a Biological Problem 4
Francis Crick, the Binding Problem and the Hypothesis of Forty Hertz 5
Gerald Edelman and Reentry Mapping 6
Roger Penrose, Kurt Gödel, and the Cytoskeletons 7
Consciousness Denied: Daniel Dennett’s Account 8
David Chalmers and the Conscious Mind 8
Israel Rosenfield, the Body Image, and the Self 11
Conclusion: How to Transform the Mystery of Consciousness into the Problem of Consciousness 11
John Searle, The Rediscovery of The Mind, 1992 12
Introduction 12
What’s Wrong with the Philosophy of Mind 12
The Recent History of Materialism: The Same Mistake Over and Over 12
Breaking the Hold: Silicon Grains, Conscious Robots, and Other Minds 14
Consciousness and its Place in Nature 14
Reductionism and the Irreducibility of Consciousness 15
The Structure of Consciousness: an Introduction 16
A Dozen Structural Features 16
Three Traditional Mistakes 18
The Unconscious and its Relation to Consciousness 18
Consciousness, Intentionality, and the Background 20
The Critique of Cognitive Reason 20
The Proper Study 21
David Chalmers, The Conscious Mind, 1996 22
Introduction: Taking Consciousness Seriously 22
Two Concepts of Mind 22
What is Consciousness? 22
A catalog of conscious experiences 22
The phenomenal and psychological concepts of mind 23
The double life of mental terms 23
The two mind-body problems 23
Two concepts of consciousness 23
Supervenience and Explanation 24
Supervenience 24
Reductive explanation 24
Logical supervenience and reductive explanation 24
Conceptual truth and necessary truth* 25
Almost everything is logically supervenient on the physics* 25
THE IRREDUCIBILITY OF CONSCIOUSNESS 25
Can Consciousness be reductively explained? 25
Naturalistic Dualism 25
The Paradox of Phenomenal Judgment 25
TOWARD A THEORY OF CONSCIOUSNESS 25
The Coherence Between Consciousness and Cognition 25
Absent Qualia, Fading Qualia, Dancing Qualia 25
Consciousness and Information: Some Speculation 25
APPLICATIONS 26
Strong Artificial Intelligence 26
The Interpretation of Quantum Mechanics 26
Copyright and Latest Update 26
Footnotes 26
The Reviews
John Searle, New York Review of Books, The Mystery of Consciousness, 1997
Consciousness as a Biological Problem
Common sense definition of consciousness - as states of sentience and awareness - is simple…
Analytic definition (in terms of an underlying essence) and establishing consciousness-matter (brain) relations is hard.
Problem 1: Cartesian Dualism seems to place consciousness outside natural science.
Eccles and others believe it is outside the explanations of science.
The ideas “mental”, “physical”, “materialism”, “idealism”, “monism”, “dualism”…are thought of as clear and that the issues have to be posed and resolved in these traditional terms. This is a source of problems. As a result of accepting this framework the reality of consciousness implies dualism and negation of the scientific world view that took 400 years to develop. This motivates many scientists (Dennett is one) and philosophers to eliminate consciousness by reducing it to something else. A small number of scientists (Chalmers, Penrose and others) accept dualism - this, too, is problematical.
Searle believes that the old categories and ingrained habits of thought need to be discarded. Consciousness is a biological problem: brain causes consciousness.
Problem 2: That the brain “causes” consciousness is “philosophically loaded” - it seems to imply dualism.
But the implication is only on the “effect temporally follows cause” notion of causality.
An example of cause-effect that is not temporal is the solidity of a table that is caused by the behavior of molecules but is not an extra event - it is a feature of the table.
Consciousness is like that - it is a feature of the brain.
Problem 3: How do publicly observable phenomena - brain processes - produce the private, subjective characteristic of all consciousness? This is the hard or philosophical problem…I called it the fundamental problem.
It is related to, but definitely not the same as the scientific problem of explaining, in detail the kinds and particulars of mental states and process on the basis of the kinds and particulars of the brains anatomical divisions and its physiological states and processes.
Problem 4: Taking the computer metaphor of the mind too literally.
Strong AI: mind is nothing but a computer program. Searle refutes this:.
The Chinese room argument - minds have semantics; programs do not - they are purely syntactical. The Chinese room showed that semantics is not intrinsic to syntax. This argument due to Searle is famous; it dates to the early 1980s.
Searle provides a newer argument, one that he thinks is more powerful and decisive: Syntax (computation) is not intrinsic to physics (computers) but is due to interpretation, i.e., it syntax is context dependent.
Francis Crick, the Binding Problem and the Hypothesis of Forty Hertz
Searle thinks that the breakthrough to explaining consciousness will come from some simple system. Still, says Searle, this does not detract from Crick’s neurobiological explanations of vision - a good choice since so much work has been done on it.
Crick’s philosophical mistakes.
Thinks the problem of qualia is about communicating the subjective aspect.
Talks eliminative reduction, practices causal emergentism - the argument against elimination is that the two features exist despite reduction but Crick advances Patricia Churchland’s mistaken criticism of the anti-reductionist argument.
Talks about the neural correlates of consciousness - which goes against reduction since a correlation is between two things - but correlation explains nothing - explanation requires a causal theory. Further, Crick sometimes denies direct perceptual awareness using a bad philosophical argument - the one that interpretations can sometimes be mistaken from the 17th century - due to Descartes and Hume.
Crick talks of the binding problem - how the brain unifies the different aspects of a perception into a unified whole. Based on work by Wolf Singer in Frankfurt and others spatially separated neurons corresponding to shape, color, movement fire in the range of 40Hz Crick and Koch speculate that these might be the brain correlates of visual consciousness. Searle thinks this is not an explanation, it is at most an explanation and makes a proper analogy to an internal combustion engine, stating that combustion correlates with motion but this is not explanation.
AM: an explanation would be that the chemical energy is really the sum of molecular potential energies that is liberated in combustion causing higher molecular kinetic energies and momentum that in turn cause greater forces to be exerted by individual molecules that aggregate as a greater total force exerted by the burning gas on a piston that causes motion. A black box macroscopic explanation could have been given but the microscopic aspect makes the analogy useful in the present context. There are two key points (1) the identification of micro-macro physical properties and (2) that at each point in the chain of events the causation is the invocation of a law - Newton’s second law of motion.
Explanation of consciousness would be similar but an ingredient is missing: what is the identification of consciousness with the physical or biological levels that do not include explicit mention of consciousness[1]. The identification could be microscopic or macroscopic or both. However it poses a problem not present in the physical case for the identification of liberation of chemical energy with motion is based on a chain of reasoning through a law of physics. Where does the identification of consciousness with the physical level come in? It need not be through a law and three solution ideas arise; (1) just as force is causally related to motion through a causal law, what are the law-like causal powers of consciousness, (2) the flip from “as if” or third person to the phenomenal or first person modes of description could well be a simple identity once enough is known about bio-physiology and about consciousness and mind, and (3) identifying the material realm as a phase or territory within a graded idealism that includes the case of classical or other materialism and, possibly, natural rather than bridging laws. An alternative to idealism is to identify a realm of experience in a field that may be unspecified. The field may turn out to be matter, being, mind…and the relation to the field may be effect or correlate (matter), phase (being), embedding or identity (mind). Lack of specification provides an overview within which specifications may be situated and related e.g. causal relationship is a case within correlation; there are various reasons for a disposition toward a causal relation but the final explanation may or may not be causal and therefore a hierarchy in which cause is situated within correlation provides a research program within which specific ideas may be tested without the rigidity of unnecessary commitment. The arrangement allows for awareness to be the world seen through itself. A final solution may be formulated from a number of solution ideas and include one or more of the above. These solution ideas, especially (1) and (3) define research projects on which I have done work.
The fundamental problem of metaphysics is not so much the question of idealism vs. materialism and so on but the question of the meaning of “idea”, “being”…and, relative to humankind, not so much the given meaning or usage but are the potential meanings and usages….
…and potential, relative to humankind, does not mean possible but, rather, what is true but not yet known.
…and the fundamental psychological issue of metaphysics is to use but not be wedded to given/received meanings, usages and knowledge.
Gerald Edelman and Reentry Mapping
“Of all the neurobiological theories of consciousness I have seen, the most impressively worked out and the most profound is that of Gerald Edelman.”
But:
“…it is possible that a brain could have all these functional, behavioral features, including reentrant mapping, without thereby being conscious.”
And, recalling Crick’s ideas:
“…the problem is the same as the one encountered before: how do you get from all these structures and their functions to the qualitative states of sentience or awareness that all of us have.”
AM: For this critique by Searle to be significant and reasonable:
Explanation of subjectivity must be tractable on scientific/material accounts.
The problem is, of course, the explanatory gap between subjectivity and brain/matter that, in scientific description, is devoid of matter.
Tractability: the gap is merely a gap and not an unbridgeable chasm.
There should be a specification of the kind of criteria that an explanation should satisfy. This follows from the fact that it is not obvious what these criteria might be - presumably the system should have certain kinds of effects or causal powers…but what are these powers and how will we demonstrate that those causal powers, even if equal to the causal powers of consciousness, imply consciousness? Of course, the criteria may not yet be known and may be tied to the explanation.
It seems to me that that criterion (set) is going to have to be magic (in the sense of insight, a change of Gestalt…but not in the abracadabra sense)…or plain obvious (seen but not recognized…); Searle’s “consciousness is a feature of the brain” is a candidate but is not yet very helpful.
Roger Penrose, Kurt Gödel, and the Cytoskeletons[2]
The main ideas of Roger Penrose as presented in The Emperor’s New Mind, 1989 and Shadows of the Mind, 1994, are:
Minds are capable of non-computable (non-algorithmic) processes, therefore minds cannot even be simulated by computers or algorithms.
The mathematical theories of classical and today’s quantum physics are computable and therefore the physical elements underlying minds and mental processes must include phenomena that will require description by some new and future non-computable physical theory.
Penrose extends the argument in (a) to quantum computers defined as machines that obey the rules of today’s quantum mechanics. The argument is that this class of quantum computers are equivalent to the class of classical computers that are enhanced by a randomizing element. Therefore quantum computers are also limited to computable operations. This is also the argument for the computability of quantum mechanics to date.
Penrose’s candidate for the new physics is quantum gravity.
Obviously, this discussion omits a wealth of detail and subtlety including some crucial issues such as how a neuron might deploy quantum behavior. The problem with the latter is the issue of the superposition of neuron computation given the disturbance of the environment by each neuron signal.
Briefly, the proposed and tentative resolution is “quantum coherence in microtubules.”
Searle’s responses:
“…from the fact that a certain type of computational simulation cannot be given of a process under one description it does not follow that another type of computational simulation cannot be given of the very same process under another description.” (p. 71).
And :”An intelligent version of Weak AI[3] should attempt to simulate actual cognitive processes. Now, one way to simulate cognitive processes is to simulate brain processes…” (p. 72) The point to Searle’s argument is that simulation of brain processes is not a simulation at the level of mathematical reasoning. Penrose’s argument, according to Searle, “shows that there cannot be a computational simulation at the level of mathematical reasoning.” Searle continues, “Fine, but it does not follow that there cannot be computational simulation of the very same sequence of events at the level of brain processes, and we know that must be such a level of brain processes because we know that any mathematical reasoning must be realized in the brain.” (p. 74).
“How is it even conceivable that his hypothetical quantum mechanics could cause conscious processes? What might the causal mechanisms be?” (p. 84).