2 Brains and Behavior Hilary Putnam Once upon a time there was a tough- ism appeared to exhaust the alternatives. minded philosopher who said, 'What is all Compromises were attempted ('double this talk about "minds", "ideas", and "sen- aspect' theories), but they never won sations"? Really-and I mean really in the many converts and practically no one real world-there is nothing to these so- found them intelligible. Then, in the mid- called "mental" events and entities but 1930s, a seeming third possibility was dis- certain processes in our all-too-material covered. This third possibility has been heads.' called logical behaviorism. To state the And once upon a time there was a nature of this third possibility briefly, it is philosopher who retorted, 'What a master- necessary to recall the treatment of the piece of confusion! Even if, say, pain were natural numbers (i.e. zero, one, two, perfectly correlated with any particular three ... ) in modern logic. Numbers are event in my brain (which I doubt) that identified with sets, in various ways, de- event would obviously have certain prop- pending on which authority one follows. erties-say, a certain numerical intensity For instance, Whitehead and Russell iden- measured in volts-which it would be tified zero with the set of all empty sets, senseless to ascribe to the feeling of pain. one with the set of all one-membered sets, Thus, it is two things that are correlated, two with the set of all two-membered not one-and to call two things one thing sets, three with the set of all three-mem- is worse than being mistaken; it is utter bered sets, and so on. (This has the ap- contradiction.' pearance of circularity, but they were able For a long time dualism and material- to dispel this appearance by defining 'one- membered set', 'two-membered set', 'three- membered set', etc., without using 'one', From R. J. Butler, ed., Analytical Philoso- 'two', 'three', etc.) In short, numbers are phy, vol. 2 (Oxford: Blackwell, 1965). Reprinted treated as logical constructions out of sets. by permission of the author. Notes have been re- The number theorist is doing set theory numbered for this edition. This paper was read as without knowing it, according to this in- part of the program of the American Association for the Advancement of Science, Section L (His- terpretation. tory and Philosophy of Science), December 27, What was novel about this was the 1961. idea of getting rid of certain philosophi- 2. Brains and Behavior 25 cally unwanted or embarrassing entities behaviorism attracted enormous attention (numbers) without failing to do justice to -both pro and con-during the next thir- the appropriate body of discourse (num- ty years. Without doubt, this alternative ber theory) by treating the entities in proved to be a fruitful one to inject into question as logical constructions. Russell the debate. Here, however, my intention was quick to hold up this success as a is not to talk about the fruitfulness of the model to all future philosophers. And investigations to which logical behavior- certain of those future philosophers--the ism has led, but to see if there was any Vienna positivists, in their 'physicalist' upshot to those investigations. Can we, phase (about 1930)-took Russell's advice after thirty years, say anything about the so seriously as to produce the doctrine rightness or wrongness of logical behav- that we are calling logical behaviorism- iorism? Or must we say that a third alter- the doctrine that, just as numbers are (al- native has been added to the old two; that legedly) logical constructions out of sets, we cannot decide between three any more so mental events are logical constructions easily than we could decide between two; out of actual and possible behavior and that our discussion is thus half as dif- events. ficult again as it was before? In the set theoretic case, the 'reduc- One conclusion emerged very quick- tion' of number theory to the appropriate ly from the discussion pro and con logical part of set theory was carried out in detail behaviorism: that the extreme thesis of and with indisputable technical success. logical behaviorism, as we just stated it One may dispute the philosophical signifi- (that all talk about 'mental events' is trans- cance of the reduction, but one knows ex- latable into talk about overt behavior) is actly what one is talking about when one false. But, in a sense, this is not very inter- disputes it. In the mind-body case, the re- esting. An extreme thesis may be false, al- duction was never carried out in even one though there is 'something to' the way of possible way, so that it is not possible to thinking that it represents. And the more be clear on just how mental entities or interesting question is this: what, if any- events are to be (identified with) logical thing, can be 'saved' of the way of think- constructions out of behavior events. But ing that logical behaviorism represents? broadly speaking, it is clear what the view In the last thirty years, the original implies: it implies that all talk about men- extreme thesis of logical behaviorism has tal events is translatable into talk about gradually been weakened to something actual or potential overt behavior. like this: It is easy to see in what way this view (1) That there exist entailments be- differs from both dualism and classical tween mind-statements and behavior- materialism. The logical behaviorist statements; entailments that are not, per- agrees with the dualist that what goes on haps, analytic in the way in which 'All in our brains has no connection whatso- bachelors are unmarried' is analytic, but ever with what we mean when we say that that nevertheless follow (in some sense) someone is in pain. He can even take over from the meanings of mind words. I shall the dualist's entire stock of arguments call these analytic entailments. against the materialist position. Yet, at the (2) That these entailments may not same time, he can be as 'tough-minded' as provide an actual translation of 'mind talk' the materialist in denying that ordinary into 'behavior talk' (this 'talk' talk was talk of 'pains', 'thoughts', and 'feelings' introduced by Gilbert Ryle in his Concept involves reference to 'Mind' as a Cartesian of Mind), but that this is true for such su- substance. perficial reasons as the greater ambiguity Thus it is not surprising that logical of mind talk, as compared with the rela- 26 Hilary Putnam tively greater specificity of overt behavior feeling is legitimately calle feeling of talk. pain.' The difficulty, of course, is that I I believe that, although no philoso- cannot have Jones's feeling at time tl- pher would to-day subscribe to the older unless I am Jones, and the time is t1. version of behaviorism, a great many From this simple observation, certain philosophers1 would accept these two things follow. For example, the account points, while admitting the unsatisfactory according to which the intension of the imprecision of the present statement of word 'pain' is a certain quality which 'I both of them. If these philosophers are know from my own case' must be wrong. right, then there is much work to be done But this is not to refute dualism, since the (e.g. the notion of 'analyticity' has to be dualist need not maintain that I know the made clear), but the direction of work is intension of the English word 'pain' from laid out for us for some time to come. my own case, but only that I experience I wish that I could share this happy the referent of the word. point of view-if only for the comforting What then is the intension of 'pain'? I conclusion that first-rate philosophical am inclined to say that 'pain' is a cluster- research, continued for some time, will concept. That is, the application of the eventually lead to a solution to the mind- word 'pain' is controlled by a whole clus- body problem which is independent of ter of criteria, all of which can be regarded troublesome empirical facts about brains, as synthetic. 3 As a consequence, there is central causation of behavior, evidence no satisfactory way of answering the for and against nonphysical causation of question 'What does "pain" mean?' ex- at least some behavior, and the soundness cept by giving an exact synonym (e.g. or unsoundness of psychical research and 'Schmerz'); but there are a million and one parapsychology. But the fact is that I different ways of saying what pain is. One come to bury logical behaviorism, not to can, for example, say that pain is that feel- praise it. I feel that the time has come for ing which is normally evinced by saying us to admit that logical behaviorism is a 'ouch', or by wincing, or in a variety of mistake, and that even the weakened other ways (or often not evinced at all). forms of the logical behaviorist doctrine All this is compatible with logical be- are incorrect. I cannot hope to establish haviorism. The logical behaviorist would this in so short a paper as this one;2 but I reply: 'Exactly. "Pain" is a cluster-concept hope to expose for your inspection at least is to say, it stands for a cluster of the main lines of my thinking. phenomena.' But that is not what I mean. Let us look at another kind of cluster- Logical Behaviorism concept (cluster-concepts, of course, are The logical behaviorist usually begins not a homogeneous class): names of dis- by pointing out what is perfectly true, that eases.