303

JOURNAL OF THE EXPERIMENTAL ANALYSIS OF BEHAVIOR 2002, 77, 303–311 NUMBER 3 (MAY)

SCHEDULES OF REINFORCEMENTWITH SKINNER

C. B. FERSTER

THE AMERICAN UNIVERSITY

To tell about the pigeon laboratory at Har-vard during the period I was there, I mustfirst describe the state of the science at Co-lumbia while I was a graduate student there.The comparison provides a ‘‘before and af-ter’’ which will help me to communicate whathappened at Harvard during the years whenB. F. Skinner and I worked on Schedules of Re-inforcement.

The pigeon lab was already operating atHarvard in the fall of 1950 when wordreached Columbia that Skinner was lookingfor someone to assist him. Columbia was theobvious place to look because there was somuch activity and excitement there about op-erant conditioning and a functional analysisof behavior. Keller and Schoenfeld had justcompleted Principles of Psychology, and the in-troductory course at Columbia was in fullswing. We learned of the impact of a labora-tory science of behavior on biological sci-ence, pressing community problems such asmental illness, education, and rearing chil-dren for a better life and a basic understand-ing of human nature. Everyone had condi-tioned a rat, read Walden Two, and most wereimpatient for a chance to try out a science ofbehavior. Some students fantasied a new In-stitute for Operant Behavior with buildings,equipment and full-time research. Othersdreamed of an actual planned communitymodeled after Walden Two where the productsof laboratory research could be lived and ap-plied. I’m sure many of today’s laboratoriesexceed what were then our wildest expecta-tions. For in those days the typical operantexperimenter either manually operatedswitches in a darkened room, or programmeda half dozen relays cannibalized from vendingmachines. A pressing instrumentation prob-lem was a reliable pellet dispenser, but re-cording problems were not serious because

From: Dews, P. B. (Ed.). (1970). Festschrift for B. F. Skin-ner (pp. 37–46). New York: Irvington. Reprinted with thekind permission of Irvington Publishers, New York.

only a small amount of behavior was record-ed. Experiments, seldom more than an hourlong, took place just before the rats were fed.

I was a third-year graduate student when,hearing of the chance to work with Skinner,I made an appointment to go to Cambridgefor an interview. I took the midnight train toBoston and wandered around HarvardSquare nervously from six in the morning un-til what I thought would be a respectablehour to appear at Skinner’s office. The inter-view was easy once I got there. We had a coke,he showed me some of the equipment in thelab, and I was scarcely aware of at what pointI knew that I was to come to work in Febru-ary. Within two hours I was on my way backto New York and Skinner was back in his of-fice writing.

I had finished almost all of my course workat Columbia and was doing exploratory ex-periments on chaining. A retractable levercame into the cage when the rat pulled achain suspended from the ceiling. Thesewere called exploratory experiments becausethey preceded the real experiment; becauseonly one or two animals were used; becausethe procedures as well as the apparatus wereconstantly adjusted during the experiments;and because it was impossible to know in ad-vance what was going to happen. Experi-ments in which an animal served as its owncontrol were not quite acceptable at Colum-bia as yet.

Because Skinner wanted me to be in Cam-bridge by the first of February, completing aPh.D. dissertation before I left posed a largeproblem. At Columbia, getting a thesis topicapproved was quite an involved process. Firstthere were informal tests with faculty and stu-dent. These consisted of discussions in thecorridor with other graduate students and vis-its to several professors’ offices. The pro-posed experiment was received very differ-ently in different places. First, there were thekind ear and probing questions of Professor

304 C. B. FERSTER

Fig. l. The relay programming and recording equip-ment for the chained VI FI equipment. There were threeparallel pairs of bars on the tables into which the relayand other control panels were fastened. The pigeon boxrested on the shelf below the table and the recorder saton a bridge across it.

Keller who listened gently until there was nomore time. Later in the day of my ‘‘test’’ withKeller, I found myself redoing the plan as Itried to explain answers to his questions. Oth-ers were not so gentle. A thesis plan also hadto pass muster of a formal departmentalmeeting. Since I had not even gotten by theinformal test when I returned from my inter-view with Skinner, it was clear that the usualprocess was much too long and labored tomeet Skinner’s deadline, so chaining was putaside, for the time being. Instead I formulat-ed a hypothesis, built equipment, ordered fif-ty genetically controlled Wistar rats, and test-ed the hypothesis that a stimulus presentduring conditioning would influence thenumber of performances the rat would emitwhen reinforcement was discontinued.

The laboratory was in operation when I ar-rived in Cambridge. Several graduate stu-dents were preparing pigeon demonstrationsfor Skinner’s introductory course and therewere several pigeon boxes with relay controlapparatus. The newest behavioral discoverywas aperiodic or random-reinforcement (var-iable-interval) schedules which were pro-grammed by a metal phonograph recordingdisc covered with plastic. A slow motor turnedthe disc. A wiper, operating on the outsidegroove of the disc, like the recording arm ofa phonograph, picked up an electric pulsewhenever the covering was scraped away. Thedistribution of scratches around the periph-ery of the disc made the variable schedule,and the number of scratches determined theaverage interval of reinforcement.

When I reported to Skinner on my first day,he showed me parts and plans for a variable-ratio programmer for Elinor Maccoby, thencompleting her Ph.D. in the Social RelationsDepartment. She needed the equipment foran experimental thesis with pigeons, whichextended the experiments on random-inter-val to random-ratio schedules as they werethen called. The programmer, already de-signed by Skinner, was to be built from a step-ping switch much along the principle of themotor-driven disc used to arrange a variable-interval schedule.

My first months in the pigeon lab were astrange contrast of days adjusting equipmentand experimental procedures for one or twopigeons, and nights at the calculating ma-chine trying log and trigonometric transfor-

mations of the thesis data to make an analysisof covariance possible. Fortunately, the in-crease of the frequency of rewards of the for-mer activity could be paced with the earlycompletion of the latter.

While I was building the variable-ratio pro-grammer, I spent the rest of the time duringmy first week in the lab exploring all of theparts in the drawers and cabinets, reorganiz-ing them according to my own habits, andlabeling them to my custom. I found a largestore of small electrical and mechanical parts:springs, phosphor bronze, string, glue, bake-lite, plexiglas, surplus relays, assortments ofcapacitors and resistors, cable clamps, lacingcord, soldering supplies, bits and pieces ofrubber and plastic, a large box of accumulat-ed nuts and bolts, small odd pieces of metal,wire and cable, surplus electronic relays andelectrical devices that could be disassembledfor parts, cardboard and paper, motors and ahost of the miscellany that seems to come inhandy at odd times for unexpected uses. Ger-brands’ machine shop down the hall hadseemingly endless drawers of bolts and nuts,cotter pins, hex nuts, brass nuts, steel nuts,lock washers, Allen nuts, Phillips head,round-head, flat-head, oval-head, and spline-head screws, wood, machine and metal

305SCHEDULES OF REINFORCEMENT WITH SKINNER

screws, brass and steel washers and lock wash-ers. All were stocked in every length, diame-ter and thread. Further down the hall werethe psycho-acoustic laboratory shops, direct-ed by Rufus Grason, where resistors, capaci-tors and all of the rest were found in the samerows of cabinets and in the same profusionof varying wattages, resistances and capaci-tance values, accuracy levels and shapes. Thepigeon laboratory already had a room dedi-cated as a shop with a drill press, two longwork benches and the usual assortment ofhand tools.

Instrumentation was easy and natural, andall components for innovative apparatus con-struction were immediately at hand. Herbachand Rademan sold surplus electrical equip-ment by mail order catalogue, even then, andit was the tradition then as it is now to scanthe catalogue each month to buy parts anddevices that ‘‘might be useful sometime.’’One of the first steps for solution of an in-strumentation problem was always to lookthrough the drawers and cabinets to see whatsuggested itself.

The physical arrangements of the labora-tory, the supplies, the equipment and theshop were important factors in determiningthe kind of research that went on. There weresufficient parts immediately on hand for con-struction to begin the moment an experi-ment required new instrumentation. Skinnerusually built the first model from what was onhand, seldom waiting because parts neededto be ordered. The prototype was usuallymakeshift and not quite reliable enough, butit served long enough to prove itself. By thenthere had been time enough to order properparts and to build a well-constructed model.

Probably the most serious and pressing in-strumentation problem we faced was the de-sign of a reliable cumulative recorder, andthe construction of enough of them to ser-vice the large number of experiments thatran concurrently. Even more recorders wereneeded because we developed the habit ofusing several at once on a single experiment,as in a multiple schedule, to treat the dataduring recording rather than by numericalmanipulations later. The first model used aLedex rotary switch to drive the pen on theperformance scale. By this time the paperdrive worked well, using a typewriter platen,with its associated mechanism for holding the

paper, and the Leeds-Northrup glass reser-voir pen solved the problem of providing areliable ink line. Twelve recorders were hard-ly completed, however, when the experimen-tal sessions lengthened because we learnedhow to sustain high rates of performance withour pigeons for ten-hour sessions or more.Experiments which recorded two or threethousand pecks at the start of our researchsoon required 100,000 or more pecks to berecorded during a single experimental ses-sion. For a long while, I spent much of mytime replacing and repairing rotary solenoidswhich lasted only a few hundred thousandoperations. The discovery of the AutomaticElectric stepping switch mechanism, whichstood up to the billions of pecks which wererecorded on each instrument, freed muchtime and energy for other purposes.

It was an enormous source of support tomove into a laboratory which Skinner had al-ready arranged and stocked. A beginner facesso many anxieties and new problems thatwithout this support I doubt that there wouldhave been enough energy both for producingthe physical arrangement of shops, suppliesand equipment that is so critical in order tobe able to do innovative research, and for ac-tually carrying out an experiment. The pi-geon lab set the pattern for all of my laterlaboratories. For example, I always saved andcarried with me a large box of nuts, screws,hardware, assorted junk and parts and devic-es that accrued when the bench top was sweptand that ‘‘might be useful someday.’’ For al-most ten years, I carried around a 244 polestepping switch (purchased from surplus fora dollar or two) before I finally threw it out.

During my first months with Skinner andthe pigeon lab, I learned a great deal abouthow to run a laboratory, design and interactwith experiments, and think through instru-mentation and research problems. The teach-ing process was so natural but subtle, that Ihad no awareness that I was learning any-thing new or that the research we were car-rying out was a departure from the existingbody of knowledge. It was not until monthslater, around the time we gave our first paperon schedules (Skinner on mixed and I onmultiple schedules), that I began to con-sciously sense that our work was extendingand departing from the current literature.

I think that part of the reason for the del-

306 C. B. FERSTER

icacy and smoothness of the learning processwas Skinner’s natural style of creating theconditions which allowed learning to takeplace rather than teaching or telling methings. In retrospect, my personal experiencein the spring of 1950 contained many exam-ples of how the laboratory environment con-tained supplementary and collateral variableswhich supported my behavior so long as theywere needed, and which faded out as I de-veloped my own ways of providing the samesupport. The first task assigned to me in thelaboratory, constructing the random-ratio(variable-ratio) programmer for Elinor Mac-coby’s experiment, served to move me intoaction at my own pace and with support. Thedevice had already been designed and thecomponents were at hand. Although it was asimple device which I could now complete inan hour or two, I spent two or three days pok-ing away at it, redoing it several times and atthe same time getting used to the color of thewalls and the other features of my new work-ing space. No one checked on the progressof the device during these several days andthe most important consequence of finishingit was its installation in the control circuits ofElinor Maccoby’s pigeon experiment.

I began two experiments as soon as I hadstraightened out the cabinets, swept the floor,and built the random-ratio programmer. Onewas variable-interval baseline with a time outbetween reinforcement and the performancethat preceded. I don’t remember now why Idid this experiment except perhaps it was theonly one I could think of. Fortunately, no oneasked me. I was surprised that the delay be-tween the performance and the operation ofthe food magazine did not decrease the fre-quency of pecking, so I continued to extendthe delay period. No one noticed this exper-iment for some time. Skinner suggested thesecond experiment. He thought we shoulddo something with ‘‘ratios’’ and we talkedabout how number of pecks could control thebird’s behavior in a ratio schedule and I sug-gested that we reinforce for a long time onFR 50 and see whether we could see the evi-dence of the reinforcement after fifty perfor-mances, when reinforcement was discontin-ued. Skinner suggested a random alternationbetween a small and a large fixed-ratio sched-ule (two-valued ratio) so that the control bythe smaller ratio would show up in the effect

on the large ratio on a continuing basis. Theidea of a stable state experiment ended thediscussion and began the experiment.

Thereafter our discussion about experi-ments occurred at ‘‘rounds,’’ usually the firstthing each morning when we toured the lab-oratory to look at the harvest from the dayand night before. This was when we discov-ered the apparatus failures, particularly in cu-mulative recorders, which were so frequentand discouraging during the early days of thepigeon lab. Failures of programming and re-cording sometimes set an experiment backthe days or even weeks that were necessary torecover the baseline. On these occasionsSkinner always commented on what causedthe failure and we discussed changes thatwould reduce the likelihood of failure in thefuture. Although both of us felt keen disap-pointment in the delay in the experiment,our remarks always concerned possible re-medial action rather than the current failureof the experiment (or perhaps the experi-menter). Rounds took thirty minutes to anhour, depending on the press of other activ-ities, and it was a lively activity with much roll-ing and unrolling of cumulative records,comment on what had happened, ooo’s andaaah’s about a new degree of orderliness andplanning of the next procedure. Conversa-tions did not include references to who hadpulled the switch, first mentioned the idea forthe experiment, built the apparatus, or pre-dicted the outcome of the experiment. Ittook almost a year before I stopped predict-ing. The pigeon really did know best what itwas he was likely to do and the conditionsunder which he would do it. Free of Skinner’spraise, I was also free of his censure, real orimagined. Yet I still had the advantage of aninspiring model I could observe, whose be-havior prompted me to greater accomplish-ments. I remember how easy it was for me totalk with Skinner about experiments and psy-chology in general. I sometimes wonderedhow it was that this young man could face thefeeling that almost anything he could doSkinner could do better. I think the reason Icould contribute my portion without uneasi-ness was that I was never evaluated, rewardedor punished; nor was my behavior ever mea-sured against his. I found Skinner’s reper-toire an ever-present source of prompts andsupports which I could use whenever I was

307SCHEDULES OF REINFORCEMENT WITH SKINNER

Fig. 2. The room where the graphs were pasted up and where schedules of reinforcement were written.

able to. It was a very fortunate young manfrom Columbia who had an opportunity tocarry out his work with so much intellectualand practical support and with such excitingchances to ‘‘brainstorm.’’ Nor was it a smallmeasure of support to be able to watch B. F.Skinner in the laboratory designing new in-struments, or to be able to turn over a prob-lem to him.

But I give the reader the wrong impressionif I suggest that there was no reinforcementfor the results of experimentation other thanthe actual behavior generated in the birds.There were many personal, natural conse-quences of completing a successful experi-ment. A successful experiment led to conver-sations about the data, the new devices wecould build, the new experiments that had tobe started and the new ways we could orga-nize our past experience from the laboratory.

When we discovered a new degree of or-derliness or an unexpected but rewarding re-sult on morning rounds, there was alwaysmuch excitement and talk about where theexperiment might go next and how to man-age the equipment for the next experimentthat was burning to be done because of thenew result. When new discoveries accumulat-

ed too fast to be digested during morningrounds, there were planning sessions whichwere always great fun and very exciting. It wasduring these sessions that I learned the valueof large sheets of paper which we used to aidour thought and to chart our progress. Everyexperimental result appeared as an entrysomeplace on paper about ten square feet insize. The theoretical structures and program-matic aspects of our work appeared as thespatial arrangement of the headings. Later,these headings were to appear as chapter andsubchapter titles in Schedules of Reinforcement.Each entry prompted rearrangements of thetheoretical pattern and suggested new exper-iments and programs which in turn prompt-ed further rearrangements of the data. Theinteractions between these theoretical exer-cises and changes in ongoing experiments inthe laboratory were continuous and consti-tuted an important reinforcer. Although al-most all of the entries on the large sheet ofpaper were in Skinner’s hand, I took part sig-nificantly by providing facts and prompts, andby reacting to the patterns which emerged.Mostly we arranged and rearranged the find-ings and procedures we had discovered andworked with, and reacted to the new experi-

308 C. B. FERSTER

mental procedures that were suggested by thearrangements. Skinner did most of the talk-ing, just as he did most of the writing, buteven when I was silent, I was always intenselyinvolved because he generally spoke for bothof us. It was sometimes like playing a well-tuned organ that could play itself if the rightkey were pressed and a properly reactive lis-tener were present. We came to share suchan extensive repertoire that not everythinghad to be said by each person. When one per-son spoke, the other frequently could havesaid the same thing a few minutes later, or hemight have been so close to saying it that asmall amount of supplementary stimulationwas enough to produce the same perfor-mance.

Our interaction as speakers and listenerswas an apt illustration of the verbal processdescribed in Verbal Behavior where Skinnerwrote, in the chapter on supplementary stim-ulation, about strengthening the behavior ofthe listener. To a degree we were in the sameposition as speakers and listeners as the pro-verbial prisoners who told jokes by code num-bers, indicating stories that they already knew.‘‘When no one laughed when the taps on thepipe indicated Joke Number Ten, it was ex-plained to a visitor that this prisoner didn’ttell jokes very well.’’

One of the unspoken rules of these think-ing, planning and theory sessions was toavoid criticism or contradiction. The perfor-mances which occurred were delicate and ofsuch high frequency that criticism or contra-diction produced a large and sudden change.I learned that there were natural consequenc-es of unproductive or incorrect suggestionsor formulations which shaped them and al-tered their frequency. Any thought was fairgame and the worst that could result from anerror, an inept or an inappropriate sugges-tion was that it would be ignored or have noconsequences in prompting or aiding otheractivities. If one or the other of us had strongbehavior which was not shared, a record wasmade on the work sheets, apparatus was built,or an experiment was started, but there wasno requirement for both to participate orspeak about it. In some cases an unsharedline of work disappeared because the perfor-mances it led to were not useful. In other cas-es it persisted successfully.

I don’t remember any experiment being

called ‘‘great’’ or ‘‘bad’’ or anyone being giv-en credit for doing something especially use-ful or valuable. Some experiments led to fur-ther planning, new apparatus, excitingconversations, new theoretical arrangementsof data and procedures or a rush to tell ev-eryone about them, while others enabled lessbehavior of this kind. I don’t know whetherSkinner was conscious of the lack of personalpraise in interpersonal relations in the labo-ratory. I certainly was not. My behavior wasgenerated by the natural reinforcement ofthe laboratory activity. But some of the grad-uate students found the absence of personalsupport difficult.

Recently a distinguished psychologist, whohad come to Harvard when he was a studentto study under Skinner in the pigeon lab, re-minded me of an incident which illustratedthe personal styles around the laboratorythen. After completing the professional sem-inar, the main classroom experience in theHarvard curriculum, he appeared beforeSkinner saying that he was ready to do re-search in the pigeon laboratory. He askedwhat he should start on. The conversationwas awkward; the student did not receive thekind of support and encouragement that heexpected, especially since he had come toHarvard for the single purpose of workingunder Skinner. Finally, in the heat of frustra-tion, he complained, ‘‘Aren’t I even going toget a pigeon box?’’ This remark galvanizedSkinner who dashed out of his office into thepigeon laboratory around the corner shout-ing, ‘‘Charlie, he needs a pigeon box,’’ andleft. I dutifully took one of the unused Searsand Roebuck ice chests we used as the shellsfor pigeon experimental spaces, handed it tohim, and left. The student was then left withthe problem of assembling all of the com-ponents and constructing the equipment heneeded. Although neither Skinner nor I re-membered the incident, the anger and dis-appointment could be detected after all theseyears. Yet he went on to complete an experi-ment which was an original departure fromthe main experimental program of the pi-geon laboratory and which still remains inthe literature as a base for much research andthinking. I don’t know whether this particularstudent would have gone on to do the samevaluable work had Skinner supported hisideas personally, or had I given him equip-

309SCHEDULES OF REINFORCEMENT WITH SKINNER

Fig. 3. The members of the pigeon staff meeting posed for a picture toward the end of one of the meetings. Leftto right are B. F. Skinner, Clair Marshall, W. H. Morse, R. J. Herrnstein, Tom Lohr, Nate Azrin, and James Anliker.Murray Sidman was visiting. Others attending frequently were Peter Dews, Ogden Lindsley, and Michael Harrison.

ment and supervised his day to day work inan experiment related to ours. But I thinkmany others would have become pale imita-tions of Skinner and Ferster rather than theoriginal, imaginative, aggressive scientiststhey did become.

The pigeon staff meeting where we re-viewed current experiments with graduatestudents and others was one of the traditionsof the laboratory. We met, usually weekly, inthe seminar room, reviewing and talkingabout one or two birds. Ogden Lindsley in-troduced the symbol of the pigeon feather atthis time when he made up a sign with a pi-geon feather that was hung on the bulletinboard on days that there were meetings. Lat-er, he sent a white feather to the charter sub-scribers of JEAB. The seminar presentationconsisted of either Skinner or me goingthrough the cumulative records, a day at atime and a bird at a time, reacting to thesmall details of the results. The substance ofthe meetings was a very detailed examinationof the results, even if some participants hadto learn to read cumulative records upsidedown. There were frequent interruptionswith questions, suggestions, or comments,

and usually a prolonged discussion at theend. When the prolonged discussion oc-curred before all of the data in the experi-ment had been covered, we continued withthe same bird the next time. Later, when stu-dents and others had experiments under way,they brought in their data in a similar way.The presentations of the pigeon staff meet-ings were seldom a summarized formal re-port of what had happened in the experi-ment, but rather an informal scanning of theraw data. I think the feeling of participatingin the formulation and identification of theresults contributed to strong interest in themeetings.

Most of the research for schedules of re-inforcement was completed by 1953, when webegan to plan a written report. As more ofmy time shifted to organizing the data andwriting, the laboratory was turned over toMorse, Herrnstein, and others at Harvard. Bythe end of 1954, Skinner and I were writingfull time. The first problem we faced was howto present the large amount of data we hadcollected, not only from long experimentalsessions and protracted experiments, but alsofrom a large number of separate experi-

310 C. B. FERSTER

ments. By the end of our research there wereabout a dozen separate experiments in prog-ress. The problem was to compromise be-tween the need to report enough detail ofour descriptive experiments and the need toreduce the bulk of the thousands of feet ofcumulative curves. Three inventions—thecollapsed record, a razor blade, and a stan-dard cardboard stock thirty inches long—gotthe final report under way. Collapsing therecord by cutting out blank paper along thetime axis allowed us to present as much asfifty to seventy-five thousand pecks in a singlefigure; the razor blade made it possible to cutthe records swiftly and effortlessly; and thecard stock permitted a storage system that waseasily handled. Skinner usually pasted rec-ords on the cards while I cut excerpts fromthe folders. Decisions about what to excerptwere made quickly, usually without much dis-cussion because we were both so familiar withthe records. Skinner took justifiable pride inhis skill and speed with a razor blade. Theultimate test was to cut on several layers ofpaper, piercing an exact number of layers.The figures were pasted up, experiment byexperiment, and the categories under whichthe figures were filed turned out to be thechapter and section headings of the book.On our best days we could do thirty figures,but this was a grueling pace which could notbe kept up. Once the figures were completed,the writing turned out to be a relatively rou-tine job of describing the main features of arecord and indicating procedures. It becameclear very early in our writing that we couldnot discuss the experiments theoretically orspell out the implications for the casual read-er.

We worked slowly at first, but the need tofinish before my scheduled departure in June1955 led us to organize our environment andto develop several ways of self-management.All our work was done in a room dedicatedto writing and not used at other times. Inter-ruptions were the first problem, which wehandled by a decision not to take phone calls.When visitors appeared at the door, we rou-tinely stepped in the corridor to speak withthem briefly. The frequency of interruptionsbecame very low and the writing room cameto control our behavior. Usually we began be-fore nine and stopped by lunch time. Therewas frequently a temptation to continue in

the afternoon when we were working espe-cially well or when the data were especiallyinteresting, but our recently acquired data onfixed-ratio performances convinced us toseek a work schedule that kept our perfor-mance at maximum frequency for the periodwe were actually writing. The procedureworked very well. There were no warm-up orinactive periods in the writing room. Natu-rally we did not write elsewhere nor did weconverse about outside matters nor do any-thing but work on schedules of reinforce-ment so long as we were in the writing room.At times the pace of the writing was so in-tense, and rewarding, that we began to con-trol our outside activities in the fear that theymight compete with or decrease the frequen-cy of writing and graph-making. Bridge, chessand late social evenings were out.

The professional record speaks for the ‘‘be-fore and after’’ of the pigeon laboratory.There were personal results too, however. B.F. Skinner has already written his feelingsabout our collaborative activities. For my part,besides the satisfaction of a very rewardingassociation, I remember most of all how Icame away from the pigeon lab with a firmlydeveloped attitude toward discovery and un-known things.

There is a fear of the unknown in researchjust as there is a fear of dealing with new peo-ple. We approach a new problem or a newperson with a repertoire that comes from ourpast experience. When we are successful, thenew person or problem differentially rein-forces our existing repertoire, and we acquirea new means of dealing with a new environ-ment. Unfortunately, the old repertoire oftencontinues without significant influence of thenew contingencies. Such a repertoire is calledcompulsive or neurotic by clinicians. The an-alogue, in research, is the experimenter whois controlled primarily by the social and pro-fessional consequences—his colleagues’ ver-bal behavior—and to a lesser degree by thebehavior he produces and measures in his ex-periment. I don’t think we were ever worriedin the pigeon lab that we would have nothingto show for our time or that an experimentwould waste time and money. The pigeon labwas a place where an unknown problem be-came an occasion which led to discovery andaccomplishment rather than a cause for wor-ry. The more a new situation could be seen

311SCHEDULES OF REINFORCEMENT WITH SKINNER

as very different from our current experi-ence, the more it signalled an experimentthat would bring results which we valued. Per-haps my experience in the pigeon lab with B.F. Skinner prompted me to write in 1958: ‘‘Apotential reinforcing environment exists forevery individual, however, if he will only emitthe required performances on the proper oc-casions. One has merely to paint the picture,write the symphony, produce the machine,

tell the funny story, give affection artfully(manipulate the environment and observethe behavior of the animal) and the worldwill respond in kind with prestige, money, so-cial response, love (and recognition for sci-entific achievement).’’1

1 Ferster, C. B. (1958, December). Reinforcement andpunishment in the control of human behavior by socialagencies. Psychiatric Research Reports, 101–118.