minds, brains and searle

METAPHILOSOPHY Vol, 17, Nos 2 & 3, April/July 1986 0026-1068 $2.00

REVIEW ARTICLE

MINDS, BRAINS AND SEARLE

CHARLES LANDESMAN

John Searle’s Minds, Brains and Science (Cambridge: Harvard University Press, 1984) is the printed version of the 1984 Reith Lectures. In six brief, lucidly written and vigorously argued chapters, Searle presents his own views, many of them presented at greater length and depth in his other writings, on some of the main issues in the philosophy of mind. In this article, I shall focus on the main theme of the lectures: how the mind is related to the brain.

By “mind” Searle means “the sequences of thoughts, feelings and experi- ences, whether conscious or unconscious, that go to make up our mental life.” (10-1 1) One central claim, presumably empirical, that he endorses is that “everything that matters for our mental life, all of our thoughts and feelings, are caused by processes inside the brain” (19), where “brain” is so used as to include the central nervous system. His reason for making the brain causally central to our mental life is that “if the events outside the central nervous system occurred, but nothing happened in the brain, there would be no mental events. But if the right things happened in the brain, the mental events would occur even if there was no outside stimulus.” (19) Here Searle is speaking of those mental events that are normally caused by events “outside the central nervous system.” In this he is simply adopting a view known even by Descartes who said that “only the brain can directly act upon the mind.”’

In asserting the unique status of the brain for the life of the mind, Searle does not mean to deny that mental events themselves cause changes in the brain. He admits that there is such a thing as mental causation. (17) “We get causation from the mind to the body.” (93) In this he also agrees with Descartes who said that “in man the brain is also acted on by the soul which has some power to change cerebral impressions. . . ”’ Although, unlike Descartes, Searle does not think that the mind is a substance that is distinct from the brain, these points of similarity in doctrine suggest that certain versions of dualism, such as Descartes’ and certain versions of materialism, such as Searle’s, make similar assumptions about the nature of mind.

The assertion of the existence of mental causation raises a problem. “How

Descartes, Philosophical Letters, trans. Anthony Kenny (Oxford: Clarendon Press)

I b i d . , p . 177. 1 9 7 0 , ~ . 103.

172

MINDS, BRAINS AND SEARLE 173

could something mental make a physical difference? . . . Are we supposed t o think that thoughts can wrap themselves around the axons or shake the dendrites or sneak inside the cell wall and attack the cell nucleus?” (17) I t would appear that this last question is merely rhetorical, calling for a negative answer. From the supposition that something that does make a physical difference in the brain does so by a physical process represented, somewhat hyperbolically, by such notions as wrapping itself around the axons or shaking the dendrites or attacking the ceil nucleus, the view that thoughts can make a physical difference in this way seems patently absurd. Yet, Searle’s answer t o the question, hyperbole apart, is in the affirmative. Causation from the mind to the body he calls “top-down causation” about which lie asserts: “But the top-down causation works only because the mental events are grounded in the neurophysiology t o start with. So, corresponding to the description of the causal relations that go from the top to the bot tom, there is another description of the same series of events where the causal rclations bounce entirely along the bot tom, that is, they are entirely a matter of neuron firings a t synapses, etc.” (93) . This implies that a mental event that bears the description “my willing t o raise my arm” and that causes an event in my brain that causes my arm t o rise has another description according t o which it is “entirely a matter of neuron firings a t synapses, etc.” But if the mental event is entirely a matter of neuron firings a t synapses, etc., then, contrary to our initial supposition, it cannot be a case of my willing to raise my arm. For the description “my willing to raise my arm” is a description in ternis other than neuron firings at synapses, etc., so if i t is true of the mental event, then there is something more t o it than neuron firings a t synapses, etc.

But perhaps I am making too much of the term “entirely.” Perhaps it is a slip. Let us cross it out . Perhaps what Searle intended t o say is that the mental event of my willing t o raise my arm also exemplifies neurophysiological features such as neuron firings at synapses,etc. But, on this interpretation, Searle’s explanation of top-down causation is no longer applicable. For if the mental event exhibits mental features or aspects that are not reducible to neurophysiological features, then the question ‘How could something mental make a physical difference?” remains unanswered. For what we want to know is how the mental aspect of the mental event can have physical consequences. Telling us that the event also has a physical aspect does not answer the question. Even if the mental aspect causes my arm to rise only be the mediation of the physical aspect, the problem of mind-body interaction is the problem of how the mental aspect causes the physical aspect to cause my arm to rise. So the problem is no t resolved, assuming that there is a problem in the first place (for it may just be a brute fact that mental aspects have physical consequences), just by saying that the physical aspect is part of the chain of causes ending with my arm rising.

Perhaps we can gain more enlightenment by turning to Searle’s account of how mental events are “grounded” in neurophysiology. Their grounding consists in the fact that they are “features” of the brain and central nervous

174 CHARLES LANDESMAN

system (19, 26). Searle distinguishes between the global features of physical systems and the micro-level elements of the same systems. For example, the liquidity of a glass of water is a global feature that is explained by the behaviour of its micro-elements, the H 2 0 molecules (20-21). In the same way, mental states and events are alleged to be global features of the brain that are caused by the behaviour of the brain’s micro-elements (“neuron firings at the synapses, etc.”) and are “realized in” the brain (22,28).

As we have seen, Searle uses two locutions for expressing his view of how the mind belongs to the brain. Mental events or states are features of the brain, and they are realised in the brain. On the basis of his various explanatory remarks, I find that there are two distinct interpretations of the relation between mind and brain that these locutions express. According to the event interpretation, a mental state is related to the brain as an event is related to the thing in which the event goes on. This seems to fit the following remark: “People actually think, and thinking goes on in their brains.” (50). A mental state, being a global feature of the brain, must be a state that is, in some way, global. Perhaps it is global in virtue of its going on throughout the brain or throughout many parts of the brain or at least throughout several of the micro- elements (e.g. neurons) of which the brain is composed. What is excluded by the global nature of mental events is their going on in a single micro-element. Now, what goes on in the brain, according to Searle, are neuron firings. “All of the enormous variety of inputs that the brain receives. . . are converted into one common medium: variable rates of neuron firing. . , [which] produce all of the variety of our mental life.” (9). Thus a mental event is a firing of two or more neurons, the exact number of which must be determined empirically.

According to the property interpretation, a mental state is a property of the brain as a whole. This is suggested by Searle when he remarks: “though we can say of a particular brain: ‘this brain is conscious,’ or: ‘This brain is experiencing thirst or pain,’ we can’t say of any particular neuron in the brain: ‘this neuron is in pain, this neuron is experiencing thirst.”’ ( 2 2 ) . It is also implied by his claim that “consciousness. . . is a real property of the brain.” (26). And finally the analogy between liquidity and water on the one hand and mind and brain on the other confirms the property interpretation.

One problem for either interpretation arises from the fact that one particular class of mental events - bodily sensations -have particular bodily locations. Thus it would appear that my pains, for example, are, on the event interpretation events that go on in the brain, and on the property interpretation, properties of the brain. But according to our common understanding, my toothache is in my tooth, not in my brain. The brain doesn’t have the right nerves for me to feel pain in it. And to say that a pain is a property of the brain would appear to imply that when I have a toothache my brain hurts. Perhaps this difficulty can be sidestepped by distinguishing two ways in which sensations are ‘in’ something, the way in which they are in the brain and the way in which they are in the part of the body where they are felt. Descartes held


some such view. “I recognize no sensation save that which takes place in the brain”3, he concludes on the basis of the phantom limb argument. However the sensation is represented by the mind to occur in that part of the body where the nerve that would normally cause the sensation is 10cated.~ So on his view, we have to distinguish the place where the sensation literally goes on from the place in which it is represented as going on. Perhaps Searle would be willing to make use of this theory or some variant of it.

Another prima facie difficulty with either interpretation is that most mental events other than sensations are, in our ordinary talk as well as in our most careful and deliberate discourse (as, say, in the novels of Henry James) ascribed to the person rather than to any part of the body or to any organ. We say, for example, that Tom is thinking rather than that Tom’s brain is thinking. It is reasonable to say that Tom could not think unless his brain is functioning properly and that when he thinks, many things are going on in his brain (i,e. neuron firings) that are causes and effects of his thinking. These are empirical claims that are supported by centuries of brain research. But they do not entail that acts of thinking are features of the brain. Searle argues that thoughts must be global features because he finds it implausible to say of some particular neuron that it thinks. Similarly we might argue that acts of thinking are global properties of the person on the ground that it is implausible to say of the brain that it thinks.

There are, however, two arguments that might be used to establish that our common ascription of mental states to the person is consistent with their belonging to the brain. The first makes use of an analogy between mental activity and other functions. Thus in response to the question “Why are you sitting there so quietly?” Tom might reply: “Because I am digesting my meal.” Here digesting is an activity that we (with perfect propriety) ascribe to Tom even though we know very well that it is an activity of Tom’s stomach and intestines. Tom’s digesting his meal is an event that simply consists of certain things going on in his digestive tract. There is nothing more to digestion than that. If, to the same question, Tom answered instead: L‘Because I am thinking about the mind-body problem,” we could make a similar point: his thinking just consists of his brain activity. What else is going on that it could consist of! After all, his thinking is a something rather than a nothing. What other candidate is there for it to be than the something that goes on in the brain?

The second argument is based on our old friend that brain in a vat.’ Let us pretend that Toni’s brain and nervous system were removed from his body and kept alive in a vat. Given what we know about the brain, we could reason- ably surmise that if Tom’s brain were stimulated in the same way that it was

Ibid., p. 37. See Meditation VI. See Hilary F’utnam, Reason, Truth and History, (Cambridge: Cambridge University

Press), 1981.


stimulated when he used to see a red balloon, then something would be going on in Tom’s brain that produces the experience like the experience of seeing a red balloon. If this surmise is correct, then one could say that in principle all that is needed for mental activity to occur is the brain. The rest of the person’s body is just the receptacle that keeps the brain alive. Thus it would be perfectly consistent with saying that Tom is thinking to say that Tom’s brain is thinking. There is no conflict between our everyday ascriptions and our scientific understanding.

But another more fundamental difficulty now begins to loom large. Searle’s claim that mental states are features of the brain is a revival of “the double- life” theory whose Cartesian version Ryle ridiculed in The Concept of Mind. If you replace Descartes’ mental substance with Searle’s brain substance, you obrain another version of the double-life theory. The mind is in Descartes’ version a ghost in the machine whereas in Searle’s it is a brain in the machine. Searle’s version has the consequence that all overt expressions of thought as in speaking out loud, writing, gesturing, and manifold other forms of human conduct are accompanied and caused by thinking to oneself, a form of thinking that we can label “brain thinking.”

One need not be a behaviorist who denies the very existence of covert acts of thinking to oneself in order to doubt that such acts invariably accompany and cause all overt expressions of thought. Introspection doesn’t support the double-life theory; one doesn’t always find silent thinking accompanying overt expressions of thought. In fact, it is common to discover what one’s thoughts really are in the very act of expressing them. Many writers find that in the act of expression, one clarifies and makes precise thoughts and ideas that had been vague and inchoate. Thus it is implausible to suppose that corresponding to every overt expression, there occurs a brain thinking of the very same thought. Yet the double-life theory requires that every overt expression of thought be accompanied by a silent thinking of the same thought, for it is the silent thinking that is supposed to explain how the overt act acquires its thought content.

If introspection doesn’t support the double-life theory either in Descartes’ or Searle’s versions, perhaps there are reasons of another sort that do. After all, we speak of written and spoken words as “expressing” our thoughts. Doesn’t this imply that there must be thoughts to be expressed independent of the expression? When we say “x expresses y” don’t we imply that x and y are distinct entities? The answer is “NO!” When I silently think to myself, I usually use words, ordinary words of English. Most people think most of the time in their native tongue. My inner thoughts usually take the form of a series of speech acts that I keep to myself. So the argument based on the use of “express” implies that they are further acts of thought that my silent speech acts express. Surely one cannot rely on the supposed idiom formulated in the word “express” to produce, as if by magic, such superfluous entities. After all, to express a thought consists just in thinking it; in this interpretation it doesn’t follow that a distinct and separate covert act of thinking must


accompany and cause the act of expression. My reasons for rejecting the double-life theory are quite consistent with there being brain events that accompany and cause the expression. But what causes an aL. of thinking - overt or covert - need not be an act of thinking. In some cases overt expressions d o express prior or simultaneous silent thoughts; i ther cases they d o not.

Searle’s theory of intentionality can be used as the basis of another argument t o support the double-life theory. Intentionality is that feature of our mental states in virtue of which they “are directed at , or about, or refer to, or are of objects and states of affairs in the world other than themselves.” (16). In his 1983 book Inrentionality, Searle distinguishes between derived and intrinsic intentionality as follows: “Since sentences - the sounds that come out of one’s mouth or the marks that one makes on paper - are, considered in one way, just objects in the world like any other objects, their capacity t o represent is not intrinsic but derived from the Intentionality of the mind. The Intentionality of mental states, on the other hand, is not derived from some more prior forms of Intentionality but is intrinsic t o the states them- ~ e l v e s . ” ~ According t o this argument, the intentionality of such overt expressions of thought as written or spoken words cannot be intrinsic; it must be derived. In more traditional terms, Searle is saying that the meaning and reference of words is conventional rather than natural. The source of derived intentionality must be something that possesses intrinsic intentionality, and these are mental states. For Searle, the mind imposes intentionality on sounds and marks that are not intrinsically intentional.’ So, overt expressions of thought must be accompanied and caused by covert mental states - brain thinking - t o possess the intentionality they do.

There are at least three major difficulties with this argument for the double- life theory. First, as we have seen, many mental states - not only thoughts but also desires and emotions - contain words spoken silently to oneself. So not all intentional mental states exhibit intrinsic intentionality. Some exhibit derived intentionality. For these mental states, Searle’s argument requires him t o postulate further mental states t o explain their intentionality. Since, in general, these further states are not introspectible or even retrospectible, we have n o independent warrant for their existence. Thus if there is an alternative explanation of derived linguistic intentionality that does not postulate such problematic entities, i t would be preferable t o Searle’s.

Second, the intentionality of particular words and sentences used in speech acts is not generally a function of the speaker’s present or past mental states. That “Caesar” in “Caesar crossed the Rubicon” refers t o the person it does has nothing a t all t o d o with my mental states as 1 utter that sentence. I

John R. Searle, Intentionality (Cambridge: Cambridge University Press, 19831, p. vii.

’ Ibid., p. 21 .

178 CHARLES L A N D S M A N

may have, a t the same time as I speak these words, a mistaken belief about who is named by “Caesar,” and I may use “Caesar” with the intention of referring to someone other than Caesar, but the conventional or standard or normal reference of this or any other word in the language is not caused by the speaker’s current or past mental activity. So if the derived intentionality of words is their standard meaning and reference, then the mental states of speakers are not able to play the role that Searle’s theory assigns to them.

If, however, by derived intentionality Searle has in mind the meaning and reference that speakers intend their words to have, what has been called speaker’s meaning, then, while we might admit that mental states - assuming temporarily that intentions are mental states - d o play an essential role, there is nothing here for them t o explain. For the phenomenon of derived intentionality in this case just is the speaker’s meaning; it is no t as if we had two items, derived intentionality and speaker’s meaning, the latter explaining the former. We just have one item, the intention with which words are used. That is the derived intentionality of words.

It is very likely that the intentions with which members of the speech community taken as a whole use words over a long period of time are among the causes of the standard derived intentionality embodied in the language. For example, someone intentionally uses an old word in a new way; the new meaning catches on and gradually spreads throughout the speech community or among some of its sub-groups; after a time, the new meaning becomes one of the standard meanings within the group. But this role for intentions in creating new standard meanings does not support the double-life theory, for once the meaning becomes established, the speaker’s current intentions play n o role in explaining derived intentionality.

But, putting aside the explanatory role of intentions, isn’t it true that every voluntary speech act presupposes that words are uttered with a certain intention or purpose? After all, isn’t the idea of acting with an intention or purpose or acting intentionally or on purpose implicit in the very concept of a voluntary action? And doesn’t this support the double-life theory at least to the extent of showing that every overt voluntary expression of thought is accompanied by an intention whose content includes the thought content?

The problem here has t o d o with the concept of intention. After all, the intention or purpose with which an act is done is a potential effect of the act, not its antecedent cause. If my intention in raising my arm is t o gain recognition, then gaining recognition may be caused by my raising my arm; i t certainly is not the cause of the action. Of course, we can speak of the mental side of an intention; we can refer t o the agent’s end-in-view, for example, meaning here the end that he had in mind or the end he thought about. To support the double life theory, it is not enough t o say that every voluntary overt expression of thought is done with an intention but in addition one must also claim that the intention with which it was done was accompanied by the agent’s covert having the intention-in-view. In general we can ask


whether every intention is accompanied by a mental state of having that intention-in-view. Introspection does not, I think, support an affirmative answer. Is an affirmative answer warranted a priori by appeal to the concept of intention itself’? This is a large question; it cannot be discussed here. It is sufficient to say that there are accounts of purposive or goal directed behavior that do not presuppose any mental entities. Perhaps it is just a contingent characteristic of creatures with minds that their purposive behavior is often accompanied by ends-in-view.

Third, it is doubtful that what explains derived intentionality musf be something that has intentionality at all, no less intrinsic intentionality. It is true that, as Searle has said, words and sentences, considered just as sounds and marks, have no intentionality. They are caused to have intentionality by their relations to other things. Now there is no reason to believe a priori that what causes something to have intentionality itself exhibits intentionality. The cause need not resemble the effect in any particular respect. A priori, what explains the meanings of words and sentences may lack all intentionality whatever. One cannot argue a priori that something’s derived intentionality must come from something with intrinsic intentionality. So the double-life theory gains no support from an examination of the concept of the ground of intentionality as such.

This brings us to Searle’s well-known criticisms of the strong artificial intelligence (AI) view that he repeats in this book. According to strong AI, “the brain is just a digital computer and the mind is just a computer program . . . The mind is to the brain, as the program is to the computer hardware.” (28). One implication of strong A1 is that “there is nothing essentially biological about the human mind. The brain just happens to be one of an indefinitely large number of different kinds of hardware computers that could sustain the programs that make up human intelligence. On this view, any physical system whatever that had the right program with the right inputs and outputs would have a mind in exactly the same sense that you and I have minds.” (28). Searle’s main objection to this view is based on the fact that the symbols employed in computer operations are specified purely form- ally. For the computer to use the program, the symbols need have no meaning whatsoever: “they have no semantic content; they are not about anything” (31). But since mental states have semantic content, the mind cannot be a computer program. “The mind has more than a syntax, it hassemantics.” (31). The fact that a computer responds appropriately to a certain verbal in- put does not imply that it understands it; i t is merely reacting to its formal or physical features, not to its meaning. For Searle, on the contrary, “understanding a language, or indeed, having mental states at all, involves more than just having a bunch of formal symbols. It involves having an interpretation, or a meaning attached to those symbols.” (33). This argument, according to Searle, “rests on a very simply logical truth, namely, syntax alone is not sufficient for semantics.” (34).

Searle does not deny that human intelligence can be realized in systems


other than the human brain. “Some other system might cause mental processes using entirely different chemical or bio-chemical features from those the brain in fact uses.” (41). He does insist, however, that “anything else that caused minds would have to have causal powers at least equivalent to those of the brain.” (40). He concludes by asserting that “mental states are biological phenomena.” (41).

Thus anything that caused minds would have to have the power to cause the intentionality or semantics exhibited by mental states in the brain. Now, one cannot say, a priori, that only biological systems have such powers. Although the only systems we now know of that exhibit such powers are biological, it does not follcw as a point of logic that such powers are restricted to biological systems. Even if, as a matter of fact, mental states are, as Searle claims, biological phenomena in virtue of being realised in the brain, it does not follow that they are “essentially” biological in nature. Moreover, even if we suppose with Searle that mental states are realised only in biological systems, it does not appear that what is biological about them helps us to understand what is mental about them. As biological phenomena, mental events are clumps of neuron firings in the brain; they are biological because they are realised in living tissue. But what makes them mental are such char- acteristics as intentionality, subjectivity, and consciousness (1 5-16). We do not understand and perhaps never will understand how the biological aspects account for the mental aspects. What do “neuron firings at the synapses” have to do with intentionality? Neuron firings are no more logically sufficient for intentionality than computer syntax is for mental semantics.

Of course a materialist such as Searle is free to claim that there is a brute fact connection between neuron firings and intentionality. Neuron firings are one type of phenomenon that goes on in the brain; intentionality is another; and the former causes the latter. That’s the whole story. But to accept the brute-fact view is to give up any attempt to understand the mental in terms of the physical. For such understanding occurs when, by understanding how the physical system operates, the mental follows as a matter of course, much as the various states of water are rendered intelligible by reference to the interactions and relations among water molecules. But as far as our present know- ledge of the brain goes, we have no idea how to get from neuron firings to mentality. So Searle’s insistence that mental states are biological phenomena has no explanatory value.

Searle is right about strong A1 as he defines it. Syntax does not entail semantics. Having said that, the question remains as to what you have to add to the syntax to get semantics. Searle thinks that what must be added are mental states in the brain with intrinsic intentionality. He thinks that what must be added is something that has semantics built right into it. As an answer that is unsatisfactory. It is no better than saying in response to the question of what you have to add to neuron firings in the brain to get states that are intentional, subjective and conscious that you have to add mental states. Such answers don’t satisfy because they don’t render the phenomenon to be explained


intelligible. They don’t help us understand how biology is relevant to the mind.

Consider, for a moment, a coininunity of interacting robots (i.e. non- biological systenis) making noises that sound like English words and sentences and doing so in such a regular way in connection with items in their environment as t o create the impression that they are producing speech acts in English. Their overt conduct appears t o exemplify semantics and intentionality. We know, let us suppose, that nothing in their interiors realises any mental states whatsoever. But Searle thinks that n o matter how closely the interconnections between the robot sounds and the environment simulate human speech acts, we still d o not have sufficient reason to ascribe genuine linguistic behavior and semantics to them. “The causal interactions between the robot and the rest of the world are irrelevant unless those causal interactions are represented in some mind or other.” (35). For Searle, the absence of mind and of mental events iniplies that the robot has n o capacity to understand the noises it produces and responds to and so is not actually speaking. I t only simulates speaking.

In general, there is a difference between doing something and understanding what one is doing. A skilled pianist may play a piece by habit without representing to himself what he is doing. He is, nevertheless, playing the piano. A calculator and a human may both multiply the same numbers and arrive at the same product. The former does not and the latter does understand what it is doing. There are some actions that do not require consciousness on the part of the agent. Perhaps speaking is such an action. If so, the robots speak.

Searle’s response would be that we don’t have actual speech aniong the robots because the sounds they produce lack meaning and/or reference and thus are not words in a language. And the reason they lack meaning and/or reference, is that the robots have n o minds and hence d o not represent the word-world connections t o themselves. But this response seems t o lead us back to the double-life theory and all the difficulties it entails. Besides if we have in mind standard or normal meaning and/or reference, we have seen that the speaker’s current mental state does not cause that. What does consciousness of the word-world connections add t o the connections that make them semantic? What does awareness of the connection between A and B do that makes the production of A a case of referring t o B? Certainly awareness in general does not produce semantics. When I utter “elephant” in front of a mouse, aware of my doing just that, it neither follows that “elephant” refers t o that mouse or even that I am using “elephant” in order t o refer t o that mouse. Sheer awareness or representation is of itself powerless t o produce semantics out of syntax.

Of course, Searle is right in saying that causal connections of themselves are insufficient to produce meaning and intentionality. If they were sufficient, every law of physics and chemistry would be a report of a semantic fact. But it does not follow that mental entities can d o the j o b either. Their intention-


ality is as much in need of explanation as any other. To say that their intentionality is intrinsic is just to produce a question-stopper that fails to render intelligible the phenomenon of meaning.

Hunter College of CUNY 695 Park Avenue New York, N Y 10021 USA

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