Jerome Bruner

A short history of psychological theories of learning Downloaded from http://direct.mit.edu/daed/article-pdf/133/1/13/1828748/001152604772746657.pdf by guest on 29 September 2021

Learning remains an elusive topic, de- form-wise? How do we learn the lay of spite the endless research lavished on it. the land? How do we learn to concen- And what we mean by it, of course, is trate our attention? shaped by how we choose to study it. And then there are questions about Concentrate on how children master differences in how learning occurs. Do their native language and you arrive at all species learn in the same way and do a very different conception of learning the bright and the dull go about it in like than had you researched how under- manner? And what about external in- graduates memorize nonsense syllables. ducements, rewards, and punishments? Does learning to ½nger a Bach cello so- Are all learning situations comparable? nata tap the same learning processes as I used to give the star performers of learning to trace your way through a the experiments I’d just completed to ½nger maze? Is all learning alike, re- my young daughter. These rats seemed ducible to a common set of principles? to develop a more open curiosity under Two learning tasks are said to be alike her magnanimous care. What, indeed, if mastering one makes mastering the does domestication do to an animal’s other easier–the so-called transfer cri- approach to learning? Were those in- terion. But what is transferred? Is it re- sights achieved by Wolfgang Koehler’s sponses? Rules? Or do we simply learn pampered chimpanzees–their ½guring how to learn, as when with enough out how to rake in an out-of-reach ba- practice we become exam-wise or tax- nana by putting two sticks together, for instance–simply the result of the , a Fellow of the American Acade- leisurely tutelage they received on that 1 my since 1954, is University Professor at New York German island of Tenerife? It used University, where he teaches principally in the to be said, only half jokingly, that Yale School of Law. With George Miller he founded stimulus-response-reinforcement learn- Harvard’s Center for Cognitive Studies in the ing theory was different from more cog- early 1960s. He has published widely, his work nitive California theory because Clark principally focusing on the interaction of mind Hull in New Haven taught his graduate and culture. His latest book is “Making Stories: students that rats “should get on with Law, Literature, Life” (2002). 1 Wolfgang Koehler, The Mentality of Apes © 2004 by the American Academy of Arts (New York: Harcourt Brace, 1926). This was originally published in German in 1917. & Sciences

Dædalus Winter 2004 13 Jerome it,” while Edward Tolman counseled his goes, is forever subject to Bruner on at Berkeley that rats need time enough to physics envy.) The atomism of learning learning pause at the choice points in a maze. theory embodies the notion that learn- And ½nally, do we learn for learning’s ing consists of the association of ideas, sake, or must we be extrinsically moti- memories, sensations, whatever; at its vated to do so? Assuming the latter, the heart is the conception of the associative Yerkes-Dodson law tells us that too bond, the linkage that co-occurrence or much or too little motivation reduces spatial proximity produces between two learning. I checked that out once myself sensations or ideas. While association-

and got a surprise. I found that very hun- ism is of ancient provenance, it had Downloaded from http://direct.mit.edu/daed/article-pdf/133/1/13/1828748/001152604772746657.pdf by guest on 29 September 2021 gry and just moderately hungry rats more recent philosophical adherents learned to ½nd their way through a suc- as well–not only Aristotle, but Locke, cession of pairs of doors. The correct Berkeley, Hume, and pére et ½ls Mills. path through was marked redundantly Indeed, by the mid-nineteenth century, in two ways: follow a left-right-left-right philosopher- Johann Frie- path, or just choose the darker door at drich Herbart had proclaimed the asso- each choice point. The hungry rats ciative bond as the keystone of the new learned only one of the two cues; the psychology. moderately hungry rats learned both. This paradigm found further, if indi- The less hungry rats had a more open rect, support in the newly burgeoning curiosity–like my daughter’s pets. brain physiology of those times. As the nineteenth century entered its last quar- Given all this, it is natural enough that ter, the older phrenology of the days of scientists would want somehow to sim- Gall and Spurzheim was reformulated in plify what we mean by ‘studying learn- terms of newly discovered cortically lo- ing.’ And, of course, the standard way of calized ‘centers’ in the cerebral cortex, doing that is to agree on some paradigm each dedicated to a particular function. that would make it possible to compare Perhaps the most compelling localiza- results. That is exactly what happened at tion study was the one conducted in 1870 the very start of learning research. But, by the German physiologists Fritsch and as often happens, rival paradigms came Hitzig. In their study, electrical stimula- into existence and, alas, this research tion of different spots in the medial- soon became a war of would-be para- lateral cortex produced particular, quite digms. Indeed, the learning theory wars ½nite motor responses: stimulating one that resulted came to dominate the psy- spot produced flexion of a monkey’s chological research scene from the latter forearm, another would turn his eyes nineteenth century until a decade after upward, still another would turn them World War II, with various ‘schools’ downward.2 If the brain were organized devising clever experiments to demon- in this localized punctate way, psycholo- strate how well their paradigm worked, gists asked, why not the mind as well? or how poorly rival ones fared. One needs to remember that the pre- There were two competing paradigms vailing philosophical view among those from the start, each with its variants. The principal one, a child of its times, 2 The classic article was Gustav Fritsch and was molecular associationism, a meta- Eduard Hitzig, “Ueber die elektrische Errig- phoric extension of the atomism of barkheit des Grosshirns,” Archiv der Anatomie nineteenth-century physics. (As the quip und Physiologie (1870): 300–332.

14 Dædalus Winter 2004 scholars was psychophysical parallelism, the beginning or end–are easily repro- Psychological 3 theories of which held that mind and brain move ducible. learning along parallel tracks. But the associative bond, even be- Their critics, however, championed tween nonsense syllables, soon came to another model–that of molar con½gura- seem mentalistic, too fragile to suit the tionism. This paradigm took as its major scienti½c taste of the times. So by the premise that mind and brain alike oper- turn of the century it was replaced by ate as integral systems controlling the Pavlov’s more scienti½cally solid ‘condi- functioning of component parts. Like its tioned reflex.’ Pavlov’s paradigm physi-

rival, it too rested its case on brain phys- calized associationism, turning its con- Downloaded from http://direct.mit.edu/daed/article-pdf/133/1/13/1828748/001152604772746657.pdf by guest on 29 September 2021 iology, for there was already plenty of tent into something more measurable evidence that overall cortical processes while preserving its associative form in- controlled localized centers–the neural tact. All his paradigm required was link- ‘mass action’ holism represented by the ing and relinking stimuli and responses: renowned Pierre Flourens. a salivary reflex, once produced by food, The brain’s mass action was analogous was now evoked by a bell signaling the to the phenomenology of everyday life– coming of food. Pavlov’s Nobel Prize in that ordinary experience transcends its physiology seemed to clinch the triumph bits and pieces. The ‘urban scene,’ after of physicalism. But Pavlov himself was all, is more than just a collection of taxis, not altogether pleased, as we’ll see later. buildings, pedestrians; its properties as a Now turn to con½gurationism, which whole shape the elements that make it had no shortage of to sup- up. was, of course, port it, dubious as many were of associa- the most direct expression of this view, tionism’s abstractness and its remote- and it had much to say about how learn- ness from ordinary experience. Con½g- ing was a matter of overall organization urationism had the support of brain re- rather than of local associative linkages. search as well, with the holistic neurolo- gy of the indomitable Flourens still very Consider now the rise of the associa- much in vogue. Also in those ½n de siècle tionist paradigm. That closing quarter times there was a rising tide of interest of the nineteenth century was a time of in how language and culture shaped many new studies of learning–mostly mind, with ½gures like Emile Durkheim concerned with the memorization of and Max Weber in the neighboring dis- lists of words or pairs of words to be as- cipline of sociology urging that culture– sociated. But it was the nonsense syllable not just individual encounters with the principally that gave associative bonding world of physical nature–also forms its scienti½c flavor. Hermann Ebbing- mind. haus used nonsense syllables in order to 3 Ebbinghaus’s 1885 classic is available in Eng- rule out past experience and ‘meaning’ lish only in brief, but representative excerpts in explanations of learning. Ebbing- may be found in Wayne Dennis, Readings in haus’s 1885 Ueber das Gedaechtnis is a te- the (New York: Appleton- dious account of learning lists of non- Century-Crofts, 1948), 304–313. Interestingly sense syllables (with Ebbinghaus him- enough, Ebbinghaus’s original monograph was published in its entirety in English translation self as the subject of most of the experi- in 1913 by Teachers College, Columbia Univer- ments). His ½ndings–for example, that sity–very much in keeping with the then dom- nonsense syllables in the middle of the inant emphasis on rote learning in American list are more slowly learned than ones at education. It has long been out of print.

Dædalus Winter 2004 15 Jerome Gestalt theory was the prime exemplar parent movement, not the light points Bruner on of the con½gurationist trend in those moving. The whole, then, is indeed dif- learning early years, though it hit its full stride ferent from a sum of its parts. only after World War I. Its credo was Now as it happens, Pavlov himself that all systems–physical, biological, came to advocate a kind of linguistic and mental–have the intrinsic character con½gurationism. How does the condi- of controlling the local elements that tioned response square with an ordered compose them. Field theory in physics phenomenon such as language? Does was its model, and its proclaimed maxim language change how stimuli are inter-

was “The whole is greater than the sum preted, how a conditioned stimulus is Downloaded from http://direct.mit.edu/daed/article-pdf/133/1/13/1828748/001152604772746657.pdf by guest on 29 September 2021 of its parts,” which the Gestaltists pro- substituted for an unconditioned one in ceeded to con½rm with a steady stream the case of human beings? Troubled by of clever studies on human . such issues in his later years, Pavlov pro- The Koehler chimpanzee studies on Ten- posed a Second Signal System whose erife were intended to make the same stimuli were not raw physical inputs, but point where learning was concerned: language imbedded in codes and cate- There was no way in which those chim- gories. Thus linguistic synonymy influ- panzees could turn a pair of sticks into a enced stimulus substitution in ordinary reaching tool by the simple ‘association’ conditioning. of elements. It took an act of to Some say that Pavlov was driven to do so, a way of con½guring the whole sit- his new views by communist ideologues uation. with prematurely Gramscian leanings, Koehler had a deep belief in the ubiq- but in fact his Second Signal System was uitousness of con½gurationism in all of quite in keeping with the European tra- nature. He launched one of his ½rst ma- dition of human studies, Geisteswissen- jor attacks on associationism by arguing schaft, rather than with Naturwissenschaft the insuf½ciency of atomism, in a book –a well-revered tradition among the bearing the forbidding, if telltale, title Russian intelligentsia. Still, structural- Ueber die physische Gestalten im ruhe und im ism was virtually the hallmark of the stationaren Zustanden (On physical con- lively Russian literary and linguistic ½gurations at rest and in stationary scene of Pavlov’s day, and the Second states). If atomism was insuf½cient even Signal System was certainly, to some de- in physics, Koehler asked, how could it gree, a response to that scene. I recall fly- serve as a paradigm for psychology?4 ing to Moscow from Paris in the 1960s He applied a phenomenon in visual per- with the celebrated Russian emigré lin- ception to make an analogy that would guist Roman Jakobson. He laughed when drive home his point: When two nearby I told him about Pavlov’s later turn and points of light are briefly flashed one af- about the accusation that he had knuck- ter the other, the eye perceives pure ap- led under to the nomenklatura. “No, no, Jerry, communist ideologues weren’t 4 For Koehler’s philosophical allegiances, see needed, just being Russian was enough. Mary Henle, ed., The Selected Papers of Wolfgang And being a Russian intellectual besides! Koehler (New York: Liveright, 1971). Perhaps Not even Pavlov could live with the idea the best and most accessible account of Gestalt that language makes no difference, that psychology’s empirical accomplishments (mostly before Hitler’s rise to power) is Kurt people learn like dogs!” Koffka, Principles of Gestalt Psychology (New Small wonder that cultural theorists York: Harcourt Brace, 1935). like Vygotsky and Luria took over after

16 Dædalus Winter 2004 Pavlov and that many of the post- all distinguished, self-professed Psychological theories of Pavlovian young studied Gestalt psy- stimulus-response learning theorists. learning chology at the Institute of Psychology in Their forte was the well-designed ani- Berlin in the years after.5 mal experiment: maze running, discrim- ination learning, operant conditioning The climax of the rivalry between asso- à la Skinner box, and the like–mostly ciationism and con½gurationism came with rats as subjects, but sometimes pi- in America in the years before World geons, and occasionally monkeys. Un- War I. Nourished by the imposing Ed- dergraduates were used as well, but

ward Lee Thorndike of Teachers Col- again, mostly in rote learning experi- Downloaded from http://direct.mit.edu/daed/article-pdf/133/1/13/1828748/001152604772746657.pdf by guest on 29 September 2021 lege, , the associa- ments–in what was referred to in my tive paradigm had flourished in the graduate student days at Harvard as . Thorndike had been a ‘dustbowl empiricism.’ It was in these postdoctoral student at one of the major days that Pavlov’s dog became a meta- centers of associationism in Germany. phor for American know-nothing anti- On his return to America (and Teachers intellectualism. College) he popularized practice and The burden of the behaviorists’ ½nd- repetition as the routes to pro½cient ings, taken collectively, was that repeti- school learning: practice and repeat as tion of a task, with suitable reinforce- you would were you memorizing non- ment for completing each trial, im- sense syllables.6 proved performance. There were sub- But the associationist research pro- tleties, to be sure–like the deleterious gram soon changed in America under effects of massing trials rather than the influence of Pavlov. J. B. Watson, the spacing them, creating interference by founder of American , pop- setting positive and negative reinforce- ularized Pavlov and gave his ½ndings an ment in a conflicting relationship, and American twist, by stressing how all the like. But the overall outcome of the learning occurred through stimulus and work, where ordinary everyday learning response. I sometimes wonder whether was concerned, was, I believe, much as it was Watson’s oversimpli½cations that I’ve stated it. I’ll return to this matter eventually drove American association- later. ist learning theorists to their zealous rig- But, as in Europe earlier, a contrarian or in exploring Pavlov’s ideas. It was the con½gurationism soon came into being. energy and determination of their re- Partly it was influenced by Gestalt theo- search that made America for half a cen- rists, now in America and sparking the tury the home of later Pavlovianism, a opposition, but it had American roots as half century dominated by the likes well, nourished particularly by Edward of Walter Hunter, Clark Hull, Edward Tolman, who was sympathetic to the Guthrie, B. F. Skinner, Kenneth Spence– work of Koehler and was a close friend of , a latter-day leader in the 5 Lev Vygotsky, Thought and Language (Cam- Berlin Gestalt group. Tolman’s brother bridge, Mass.: mit Press, 1962); Aleksandr Romanovich Luria, The Role of Speech in the Reg- Richard, moreover, was a distinguished ulation of Normal and Abnormal Behavior (New nuclear physicist and shielded him well York: Liveright, 1961). from old-fashioned atomistic notions– and, indeed, from physicalistic tempta- 6 Edward L. Thorndike’s classic is the three- tions. Tolman, from the start, was a cog- volume , which appeared in 1913–1914. nitivist.

Dædalus Winter 2004 17 Jerome Tolman’s ½rst major book appeared maps are not mirrors of the happen- Bruner on in 1932 and it quickly gained adherents stance of our encounters with the world, learning among the discontented, and there were but a record of our strivings and what plenty of them. His students–notably has proved relevant to their outcome. David Krech, but many others as well– His views in this sense were basically also joined the battle against associa- pragmatist, perhaps because of his years tionism. By World War II, there was vir- of exposure as a psychology graduate tually open conflict in America between student to Harvard’s pragmatist philoso- con½gurationist and associationist learn- phers, particularly C. I. Lewis, whom he

ing theorists–the ½rst holding that greatly admired. Following Tolman’s Downloaded from http://direct.mit.edu/daed/article-pdf/133/1/13/1828748/001152604772746657.pdf by guest on 29 September 2021 learning is principally a task of organiz- lead, David Krech went to the extent of ing knowledge from the top down, the proposing that learning is hypothesis second insisting that it is accreting it driven, not just passive registration. from the bottom up. The con½guration- Even rats, Krech tried to show, generate ists, though still a minority, had been of- hypotheses.8 ½cially well received on the American It’s revealing to compare Tolman with scene when they fled Hitler’s Europe. the leading, perhaps most radical associ- Koehler was invited to deliver the Wil- ationist behaviorist of the same period, liam James Lectures at Harvard, and B. F. Skinner. Skinner was surely as com- Kurt Lewin became virtually a cult ½g- pelling in defense of operant condition- ure in . The displaced ing as Tolman was of cognitive map the- members of the old Gestalt group were ory. His central concept was the operant soon well placed in leading American response–an act not initially under the universities. They made commonsense direct control of some particular feature phenomenology seem commonsense of the immediate environment. An ex- rather than arcane, an achievement ample of an operant response is provid- given the hold of behaviorist American ed by a starting pigeon in a Skinner box psychology. Learning began to be under- whose pecking of the button on the stood as grasping things in context, not box’s wall either produces or fails to pro- in bits. duce a reinforcement (a grain of seed, Take Edward Tolman’s research as an say). Any reinforcement increases the example. He taught that learning is like likelihood of the operant response mapmaking and that to learn is to organ- occurring again, the level of likelihood ize things in the light of their utility for depending upon whether the reinforce- achieving ends. In “Cognitive Maps in ment always follows the response or Rats and Men,” his still renowned Re- does so only sometimes, and whether it search Lecture to the Berkeley faculty in does so regularly (periodically) or irreg- 1947, Tolman claimed that trial and error is not so much acting out habits to dis- ry, 1932). His Berkeley lecture was later elab- cover which are effective, but rather a orated in his International Congress address, looking back and forth to get the lay of “Cognitive Maps in Rats and Men,” Psychologi- the land in order to construct a solution. cal Review 55 (4) (1948): 189–208. That is why he urged his graduate stu- 8 Krech’s bold study (written under his origi- dents not to rush their rats through the nal name) is I. Krechevsky, “‘Hypothesis’ ver- maze.7 He believed that our cognitive sus ‘Chance’ in the Presolution Period in Dis- crimination Learning,” University of California 7 Tolman’s most influential book was Purposive Publications in Psychology 6 (1932): 27–44. Behavior in Animals and Men (New York: Centu-

18 Dædalus Winter 2004 ularly (aperiodically). Partial aperiodic sic sense died around 1960–though Psychological theories of reinforcement, for example, evokes a there are still Skinnerians who stalwart- learning rather more persistent response than ly continue to publish operant ½ndings, one might expect, though Skinner would mostly for each other. I know of no more scoff at interpreting such persistence as Tolmanians or Hullians.11 hope springing eternal. Learning, in It was the cognitive revolution that Skinner’s austere terms, is under the sole brought down learning theory or, per- control of schedules of reinforcement: haps, focused attention elsewhere. After reinforcement can only be positive; pun- 1960, say, stimulus-response learning

ishment does not affect learning. And theory seemed quaintly stunted, Downloaded from http://direct.mit.edu/daed/article-pdf/133/1/13/1828748/001152604772746657.pdf by guest on 29 September 2021 that is about it. As Skinner would some- hemmed in by its own self-denial. As for times say, a bit ironically, learning more molar, cognitive learning theories, scarcely needs a theory.9 many of their ideas were restated and Not all behavioral associationists, to absorbed into general cognitive theories be sure, shared Skinner’s disdain for the- such as Newell and Simon’s on problem ory. Clark Hull at Yale, indeed, elaborat- solving, or Bruner, Goodnow, and Aus- ed his theory into a highly re½ned set of tin’s on thinking, or Miller, Galanter, axioms about what constitutes positive and Pribram’s on planning.12 By the lat- and negative reinforcement, what makes ter 1960s, learning was being translated a conditioned stimulus generalize along into the concepts of information pro- a certain gradient, how organisms an- cessing, with no compulsion to elevate ticipate reinforcers, and the like–all in one kind of learning over another in rather exquisite and specialized detail. terms of its ‘basic’ properties. Certainly, His ½rst books–the 1943 Principles of Be- the old wars were over. And so, interest- havior and the more triumphally titled ingly, were the old rat labs and their 1952 A Behavior System–bristle with ta- ubiquitous mazes. bles and idealized learning curves and As I reflect on the transition period, I with abstract formulae for relating those think that it was the study of language ½ndings to his central axioms–perhaps and particularly of language acquisition a prophetic effort to devise a mathemati- that precipitated learning theory’s de- cal model of learning, the preoccupation cline. Language use and its acquisition of computational psychologists a gener- are too out of reach of piecemeal S-R ation later.10 learning: efforts to bring them into the fold soon become absurd, and linguists The conflicts between Hull and Skin- have mostly dismissed them as such. ner, and between both of them and Tol- man, were the last battles of the learning 11 The most detailed and authoritative volume theory wars. Learning theory in the clas- on the classic learning theories is Ernest R. Hil- gard, Theories of Learning, 2d ed. (New York: Appleton-Century-Crofts, 1956). 9 B. F. Skinner, “Are Theories of Learning Necessary?” Psychological Review 57 (1950): 12 Alan Newell and Herbert A. Simon, Human 193–216. Problem Solving (Englewood, N.J.: Prentice Hall, 1972); Jerome Bruner, Jacqueline Goodnow, 10 Clark L. Hull, Principles of Behavior (New and George A. Austin, A Study of Thinking (New York: Appleton-Century-Crofts, 1942) and A York: Wiley, 1956); George A. Miller, Eugene Behavior System: An Introduction to Behavior The- Galanter, and Karl Pribram, Plans and the Struc- ory Concerning the Individual Organism (New ture of Behavior (New York: Holt, Rinehart, and Haven, Conn.: Yale University Press, 1952). Winston, 1960).

Dædalus Winter 2004 19 Jerome The contemporary linguistic assault on sounds than of foreign ones. And so it Bruner on associationist learning theory began does: French babies babble in French, learning with ’s gloves-off criti- Spanish in Spanish, etc. With such cal review of Skinner’s Verbal Behavior.13 experiments, one tests in context, not in But the mentalist, problem-solving em- a maze, and knows without extrapola- phasis it introduced has now expanded tion whether the experiment has any beyond language as such. One now asks bearing on real learning by real people in whether cultural codes are learned in real life. some language-like way. Neither psy- Shall we conclude, then, that three-

cholinguistics nor cultural psychologists quarters of a century of warfare between Downloaded from http://direct.mit.edu/daed/article-pdf/133/1/13/1828748/001152604772746657.pdf by guest on 29 September 2021 think of learning in the old-fashioned associationist and con½gurational learn- learning-theory way. ing theories taught us little or nothing I think it would be fair to say that, about the real nature of learning? That under this new dispensation, more has would be a mistake. been learned during the last three de- Both Pavlov’s dogs and Koehler’s cades about language acquisition than chimpanzees did, in fact, learn, though in any prior century–more, indeed, than in different ways and in different cir- in all of them combined. And it’s well to cumstances. And we have ample reason remember that the flood of research that to suspect that neither of their approach- made this possible was precipitated by es can be reduced to the other. In the the linguist Chomsky, not by a learning next turn of things perhaps we will ½g- theorist. ure out how to put them together. But of The turn to language, moreover, has one thing at least I am quite convinced. shifted learning-related research away You cannot strip learning of its content, from many of the older, arti½cial experi- nor study it in a ‘neutral’ context. It is mental paradigms–mazes, paired-asso- always situated, always related to some ciate word lists, nonsense syllables, and ongoing enterprise. Perhaps there is no the rest. Let me give an example: the such thing as ‘learning in general’–and prediction that children must be so early perhaps that is what we should learn tuned to the structure of their native lan- from Pavlov’s dogs, Koehler’s chimps, guage that they pick up its phonemic dis- and the disputes over learning that they tinctions in parental talk even before once symbolized. they learn to understand or talk the language proper. It is a prediction that grows out of linguistic and developmen- tal theory. And you can test it in context directly–by seeing whether childrens’ prelinguistic babbling has a higher fre- quency of native-language phoneme

13 B. F. Skinner, Verbal Behavior (Cambridge, Mass.: Press, 1947). Chom- sky’s structuralist-mentalist views were ½rst published in his Syntactic Structures (The Hague: Mouton, 1957). His frontal attack on Skinner’s Verbal Behavior (in Language 35 [1959]: 26–34) only two years later came as a rather unexpect- ed, though scarcely a conceptual, surprise.

20 Dædalus Winter 2004