I will begin with contemporary materialism. Searle levels a pretty serious offensive against materialist theories of mind in the first half of the book or so. Versions of materialism have been dominating the philosophy of mind (and much of academic philosophy generally) for the bulk of the 20th century and into the 21st, so Searle's going against the grain here was no way to guarantee popularity with his contemporaries. Searle is confident in his position though, and says with characteristic candor, "How is it that so many philosophers and cognitive scientists can say so many things that, to me at least, seem obviously false?" (p.3).
Searle considers seven popular materialist theories of mind in the book: logical behaviorism, type-identity theory, token-identity theory, black box functionalism, strong artificial intelligence, eliminative materialism, and naturalizing intentionality. Searle criticizes these seven theories primarily because they deny what is obviously true about the mind: that the mind intrinsically possesses subjective properties. He suggests that these seven materialist views are wrongly aiming for an understanding of the mind that is totally objective, largely because our intellectual community equates "scientific" with "objective." Searle writes:
"[T]here is a persistent objectifying tendency in contemporary philosophy, science, and intellectual life generally. We have the conviction that if something is real, it must be equally accessible to all competent observers" (p.16).All of the materialist models of mind considered in the book share this motivation for objectivity. In one way or another, these models try to "redefine," "reduce," "replace," or outright "eliminate" the subjective aspects of the mind. The point of this is to end up with an account of mind that is thoroughly "objective," and therefore, "scientific." Searle, however, disputes this objectifying tendency by pointing to the obvious facts of our personal, subjective experiences:
"This assumption [of objectivity] has proved useful to us in many ways, but it is obviously false, as a moment's reflection on one's own subjective states reveals" (p.16).What Searle attempts to make plain in the book is that subjectivity is an intrinsic and inseparable feature of the mind, and thus any attempt to carve the subjective off of our understanding of the mind is simply going to miss the essence of mind altogether. This is why he says all of these materialist models of mind "leave out the mind" or "deny the existence of the mind." He therefore proposes that subjectivity is a bona fide element of what is "real," and seeks to preserve the subjective properties of mind in his account. As far as I am concerned, he is plainly right, and in good company with Thomas Nagel's similar position in The View from Nowhere (1986), where Nagel writes the following:
"I have argued that the seductive appeal of objective reality depends on a mistake. It is not the given. Reality is not just objective reality. Sometimes, in the philosophy of mind but also elsewhere, the truth is not to be found by travelling as far away from one's personal perspective as possible" (p.27).To the extent Searle is right that the seven materialist accounts of mind discussed do in fact ignore or eliminate subjectivity from their accounts of mind, he seems right to conclude that they are all therefore inadequate. I agree with both Searle and Nagel that the subjective is just as much a component of our universe as the objective--part of its ontology--and the mind is obviously intrinsically subjective: no one has the capacity to "get inside" the mind of another person or "know what it's like" to be another person from the "outside." Any account of mind that misses this essential feature of mind will, for that reason, fail to be a successful account. The materialist accounts Searle discusses arguably do attempt to dispense with the subjective essence of mind; they are, therefore, most likely false.
Both the acceptance of the mental as essentially subjective and the rejection of contemporary materialist accounts of mind are about as far as Searle and I agree, however. Having rejected contemporary materialist models of mind, Searle does not embrace some form of dualism--e.g. some kind of "Cartesian" non-physical/spiritual account of mind, following Rene Descartes. To my disappointment, Searle offers no serious argument against substance or property dualism. He rather rides the wave of popular opinion and simply considers the view a non-option. Here is a representative sample of statements in his book that capture his attitude of Cartesian dualism:
"Dualism in any form is today generally regarded as out of the question because it is assumed to be inconsistent with the scientific world view" (p.3).
"I believe one of the unstated assumptions behind the current batch of views is that they represent the only scientifically acceptable alternatives to the antiscientism that went with traditional dualism, the belief in the immortality of the soul, spiritualism, and so on" (p.3).
"[W]e have a terror of falling into Cartesian dualism. The bankruptcy of the Cartesian tradition, and the absurdity of supposing that there are two kinds of substances or properties in the world, 'mental' and 'physical,' is so threatening to us and has such a sordid history that we are reluctant to concede anything that might smack of Cartesianism" (p.13).As a work of philosophy--and of philosophy of mind, particularly--Searle's superficial opposition to Cartesian dualism is disappointing. His readers are not given an evaluauable argument against dualism; they are instead given a sort of "prevailing sentiment" amongst contemporaries. Here I sympathize with Daniel Robinson of Oxford when he wrote in his paper Consciousness: The First Frontier (2010, Theory and Psychology) the following:
"Descartes is among the most libeled of all philosophers. His so-called 'errors,' 'fallacies,' and 'mistakes' continue to be the subject of learned articles and whole books. Very little in this literature adequately comprehends Descartes’s metaphysics" (p.12).Given the looseness with which Searle rejects Cartesian dualism in the book, I would throw The Rediscovery of the Mind into the literature Robinson refers to.
In any case, Searle outwardly rejects both the popular versions of materialism and all versions of dualism. This puts him in a fairly tough spot because he needs to develop his own thesis in a way that does not collapse into one of the materialist or dualist views he already rejects. Searle is rather confident that he successfully managed to do this in the book, but I remain unconvinced.
Let me now turn to Searle's thesis and my criticisms of it. In Searle's words, this is what he wishes to assert about the mind:
"Mental phenomena are caused by neurophysiological processes in the brain and are themselves features of the brain. To distinguish this view from the many others in the field, I call it 'biological naturalism.' Mental events and processes are as much part of our biological natural history as digestion, mitosis, meiosis, or enzyme secretion" (p.1).Now, as I see it, there are two major claims in this thesis worth clarifying: (1) Mental phenomena are caused by neurophysiological processes in the brain, and (2) Mental phenomena are themselves features of the brain.
With respect to (1), Searle clearly holds that the brain produces consciousness. This is to say, he thinks that the fundamental particles of the brain (protons, neutrons, electrons, etc.)--all of which are not themselves conscious--interact with each other according to the laws and forces of nature to bring about phenomena of conscious experience. To put the claim another way, Searle holds that no conscious state could exist without a brain (or something brain-like) to produce it. Searle writes, "It seems to me obvious from everything we know about the brain that macro mental phenomena are all caused by lower-level micro phenomena. There is nothing mysterious about such bottom-up causation; it is quite common in the physical world" (p.125-6). He confesses that he has no idea how the brain causes consciousness, but he thinks, given enough time and technology, neuroscientists will eventually figure out how this works.
With respect to (2), Searle often uses the analogy of H2O molecules and solidity/liquidity to illustrate what he means: "[Consciousness] is an emergent feature of certain systems of neurons in the same way that solidity and liquidity are emergent features of systems of molecules" (p.112). What is important to notice is that solidity/liquidity are features of molecules, not entities wholly distinct or separable from the molecules. Similarly, subjective mental states are not, on Searle's view, wholly distinct or separable from the relevant brain molecules. Searle says, "Consciousness is not a 'stuff,' it is a feature or property of the brain in the sense, for example, that liquidity is a feature of water" (p.105). Just as H2O molecules can be either solid or liquid depending on certain conditions, so brain molecules can be in different subjective mental states depending on certain conditions.
I find both Searle's claims (1) and (2) to be unconvincing. The main reason I find them unconvincing is common to both claims, and my reason is this: Both claims (1) and (2) fail to resolve the conceptual problem inherent in merging objectivity and subjectivity. The conceptual problem I have in mind is this: For an entity or property to be objective, it must exist in a way that is "observer independent"; that is, its mode of existence permits its properties or features to be known or observed from the "outside" by different observers. Put another way, something that exists objectively is "open" to observation from the "outside." Conversely, for an entity or property to be subjective, it must exist in a way that is "observer dependent"; that is, its mode of existence permits its properties or features to be known or observed only from the "inside" by one observer's point of view--the observer who is the subject of perception. Put another way, something that exists subjectively is "closed" to observation from the "outside." It might be tempting to think of subjective and objective as conceptual opposites (i.e. that subjective is the negation of objective and vice versa), but I do not think that is accurate. I instead think of subjective and objective as mutually exclusive, like circles and squares: e.g., if something is a square, it is not a circle; if something is a circle, it is not a square. Likewise, if something is subjective, then it is not objective; if something is objective, then it is not subjective. In other words, something cannot be both objective and subjective simultaneously.
The problem for Searle is that he has to somehow merge objectivity and subjectivity together, which seems conceptually impossible. With respect to his claim (1)--that mental phenomena are caused by neurophysiological processes in the brain--he needs to claim that the brain (whose mode of existence is objective) can cause mental states (whose modes of existence are subjective). He needs the objective to cause the subjective. Something objective must possess the resources to bring something subjective into existence. Put another way, he needs the subjective to depend on the objective--the subjective comes from the objective. He needs something that can be observed from the outside (brain stuff) to fully bring into existence properties or features that cannot be observed from the outside (mental states). He needs the cause (brain stuff) to bring about an effect (mental state) that possesses a fundamentally different mode of existence. As hard as I try to give Searle the benefit of the doubt and make his objective-to-subjective proposal coherent, I simply cannot comprehend how it could be so. Notice that we have no other example of objective-to-subjective causation to refer to. Every other instance of causation we observe in the world is either of the form objective-to-objective (e.g. fire [objective] causes ice [objective] to become liquid water [objective]), or subjective-to-subjective (e.g. a memory that yesterday was Tuesday [subjective] causes the belief that today is Wednesday [subjective]). I therefore find Searle's claim that neurophysiological processes in the brain (objective) cause mental phenomena (subjective) incomplete at best and outright incoherent at worst. He seems to merely assert that such a state of affairs is possible without resolving this conceptual problem.
It might be worth contrasting Searle's causal claim with the rival substance dualist's claim. The dualist can assert that there is objective-to-subjective causation (like lightwaves stimulating the retina causing subjective visual experience of color) by virtue of an interaction between two independently existing entities, the body and mind. The physical body, according to dualism, exists "on its own" without any dependence on the mind; likewise, according to dualism, the mind exists "on its own" without any dependence on the body. The body, therefore, does not bring the mind into existence, nor does the mind bring the body into existence. Causation between mind and body, then, is a kind of interaction between two entities. The mind is not "anchored" in the physical, so there is no need to explain the mind by way of the physical. Thus, the dualist does not have to equip the objective properties of the brain with the power to create subjective states of mind; the dualist only has to say that the objective properties of the brain can interact with the subjective properties of the mind. Granted, the dualist position has difficulties of its own, but I merely wish to point out that these views are constantly in competition with each other, so they should be considered in tandem.
Searle's claim (2) suffers a similar fate. Claim (2)--that mental phenomena are themselves features of the brain--requires that the brain simultaneously have both objective and subjective modes of existence. The brain is both "open" to observation from the outside and "closed" to observation from the outside. When a neurosurgeon looks at a living brain, the same particles that make up that brain possess both objective properties he can observe (like size, shape, color, density, etc.) and subjective properties he cannot observe (like hopes, fears, beliefs, etc.). Note that it is not that the subjective properties are simply "hidden" from the neurosurgeon; it is rather that the subjective properties are entirely inaccessible in principle from the neurosurgeon--the subjective properties exist in an entirely different way than the objective properties. Nevertheless, Searle wishes the reader to believe that the same brain particles that possess the objective properties the neurosurgeon can observe also possess subjective properties the neurosurgeon cannot possibly observe. However, the brain particles themselves can (somewhat surprisingly) observe the subjective properties of the brain particles. I propose that this state of affairs is conceptually incoherent. How could it be that the same entity (the brain) possesses a mode of existence that is at once objective and subjective? How does the brain accomplish this? How does it "cross over" into both modes of existence without splitting itself into pieces? It seems to me this is like saying the same thing is simultaneously a circle and a square. The objective and subjective seem mutually exclusive just like circles and squares. Searle's assertion that these are "properties" or "features" of the brain does not alleviate this mutual exclusivity. If something has the property or feature of "circularity" it cannot also have the property or feature "squareness." An entity must be entirely committed to one or the other; we can't just smear them together and call the problem "solved." Searle unfortunately does not discuss this sort of problem in the book; he basically leaves claim (2) as a bald assertion.
Furthermore, his analogy with H2O and liquidity fails to resolve this issue as well. In the case of H20 and liquidity, both the H2O molecules and the feature of liquidity possess objective modes of existence. H2O never needs to "cross over" from an objective mode of existence to a subjective to acquire the property "liquidity." This means there is nothing inconsistent or mutually exclusive about something's being both H2O and liquid. Analogously, there's nothing inconsistent or mutually exclusive about taking a bunch of circular discs (say, drink coasters) and arranging them into a square-like shape on a table. Even though each coaster is itself circular, a square shape can "emerge" by virtue of the aggregate's arrangement. What would seem inconsistent, though, is the claim that each circular coaster by itself exists objectively, but the aggregate arrangement on the table exists both objectively and subjectively (or has both objective and subjective properties). How would the aggregate shape "cross over" from a purely objective mode of existence into the subjective? The H2O/liquidity analogy offers no clarification on this issue at all because it nowhere introduces subjectivity into the picture. Even though I can perfectly well accept the idea of "emergence" as illustrated by liquidity emerging from H2O molecules, I still cannot comprehend how subjectivity can "emerge" from purely objective antecedents, nor further how the subjective properties can occupy the same space at the same time as that of the objective properties.
It is again worth contrasting Searle's view with the substance dualist's view. The dualist, quite clearly, is at no risk of asserting that the subjective and objective coexist simultaneously within the same entity, for the dualist places the objective within the physical brain and the subjective within the non-physical mind. The brain, therefore, is fully committed to an objective existence, whereas the mind is fully committed to a subjective existence; there is no violation of the mutual exclusivity of the subjective and objective under dualism.
My impression of Searle's project is that he wants to preserve what is plainly evident about the mind (subjective states of awareness) while also preserving what he finds plainly evident about our overall "scientific worldview" (determinate laws of causation, rejection of spiritual entities). Philosophers who also have attempted to preserve the obvious subjective states of mind have often gravitated towards a form of dualism (either property or substance) because, among other reasons, I think they recognize the problem inherent in trying to merge subjectivity and objectivity together. Searle, though, steadfastly rejects dualism. Philosophers who also have attempted to preserve a unified, causally closed, mechanistic-like time-space continuum have gravitated towards one of the forms of materialism Searle discussed and rejected because they also recognize the trouble in attempting to merge subjectivity and objectivity together. Searle, however, strongly rejects these materialist views as well. In a sense, Searle wants to have his cake and eat it too. He wants to siphon off both the best parts of dualism (embrace of subjective states of mind) and the best parts of materialism (the so-called "scientific worldview") and, essentially, smear them together. In order to do this, Searle even goes so far as to attack our traditional vocabulary words because he thinks they artificially structure our thinking into conceptual opposites:
"The vocabulary is not innocent, because implicit in the vocabulary are a surprising number of theoretical claims that are almost certainly false. The vocabulary includes a series of apparent oppositions: 'physical' versus 'mental,' 'body' versus 'mind,' 'materialism' versus 'mentalism,' 'matter' versus 'spirit.' Implicit in these oppositions is the thesis that the same phenomenon under the same aspects cannot literally satisfy both terms" (p.14).I did not catch a place in the book where he lumps the terms "subjectivity" and "objectivity" into the same criticism as the terms listed above, but I think it is likely that he would apply the same criticism to the terms objective and subjective. In other words, I think Searle would respond to me by saying there is no inherent problem in claiming that the same phenomenon could simultaneously satisfy both the terms subjectivity and objectivity. He would say that my inability to merge these two terms together is a product of my inheriting a traditional vocabulary or set of conceptual categories from the last several hundred years of philosophical thought that is almost certainly false. In short, my whole way of thinking about the problem is flawed at the core.
Now, Searle's move here strikes me as rather desperate. The scope of his argument is quite sweeping, as he is attacking our fundamental conceptual understanding of reality and logic. Thinking in terms of conceptual opposites seems to me like a perfectly reasonable way of understanding reality. But, of course, Searle could claim it only seems reasonable to me because I'm caught in the mire of the faulty conceptual framework he wishes to challenge. As such, Searle's claim becomes a claim that I simply do not have the power to evaluate. Any attempt at evaluating his argument would apply the very conceptual apparatus Searle says is broken, so the use of a broken evaluative device can only yield faulty conclusions. This is analogous to using a rubber yardstick to measure distance: the measuring device itself makes accurate measurement impossible. What Searle's argument requires, therefore, is that one accept his criticism of our conceptual framework (i.e. reject our traditional conceptual categories) without evaluating his criticism through that same conceptual framework--something that amounts to accepting his claim without any evaluation whatsoever. I, however, see no good reason to do this. Why, for example, should I take the mutual exclusivity of "subjective" and "objective" to be false? Conceptually, they are wholly distinct from one another, just as circles and squares are wholly distinct. I do not believe that Searle would take his criticism of our vocabulary so far as to say we are wrong to think circles and squares are mutually exclusive. If that is true, though, on what grounds should I suppose that "subjective" and "objective," "body" and "mind," or "physical" and "mental" are not likewise mutually exclusive? As I form the concepts "subjective" and "objective" in my mind, I find that, under no circumstance, can I faithfully combine them into the same concept. If I am right about that, then why should I nevertheless agree with Searle that the brain, under the same aspects, can literally satisfy both subjective and objective? Searle needs me to simply "overlook" or "ignore" this problem by chalking it up to a faulty conceptual apparatus, but the apparatus does not seem to be faulty for any reason other than it might lead to philosophical dualism. Conversely, suppose Searle does go so far as to say circles and squares are not really mutually exclusive: the same entity under the same aspects can satisfy both the terms "circle" and "square." If he were to go this route, I think we would have a clear reductio ad absurdum on our hands. Supposing that the same shape can be both a circle and a square quite clearly violates the principle of non-contradiction, one of the fundamental principles of logic.
So, it seems to me Searle has only two options for resolving the problem I site in merging subjectivity and objectivity together in the brain. He can either (a) accept that some concepts are mutually exclusive (like circles and squares) but reject that subjective and objective are mutually exclusive, or (b) reject that any two concepts are ever mutually exclusive, including circles and squares. Neither of these options is promising. Option (a) seems arbitrary because it accepts the concept of mutual exclusivity, but denies it in the case of subjective and objective for no principled reason; option (a) simply seems to reject mutual exclusivity for the sole purpose of avoiding dualism. Option (b) is simply absurd because it defies the very foundation of logic and reasoning: the principle of non-contradiction. I conclude that Searle's biological naturalism fails to resolve the subjectivity/objectivity problem and therefore also fails to adequately resolve the mind-body problem.
In sum, Searle's The Rediscovery of the Mind remains a worth-while read for those interested in the philosophy of mind. Searle's criticisms of prevailing materialist models of mind are well-executed and informative. The fact that he seeks to preserve salient features of mental life, like subjective awareness, is respectable. His treatment of property and substance dualism, however, is superficial and therefore disappointing. His own view, biological naturalism, strikes me as an attempt to merge the spirits of materialism and dualism together while denying that this creates any conceptual problems. He attempts to sidestep the conceptual problems of merging them by rejecting the vocabulary words that imply conceptual opposites, such as "materialism," "monism," and "dualism," supposing that the conceptual problems of his view will evaporate in the process. This move, though, seems to me arbitrary at best, and incoherent at worst. As a result, biological naturalism is a novel, but ultimately unsuccessful, account of consciousness.