B. F. Skinner, Organism

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

A. Charles Catania

B. F. Skinner illustrated the power of behavior analysis by turning it upon his own behavior. This article considers parallels in the life and work of Charles Darwin and places Skinner's views on life and death in the context of his selectionist paradigm for psychology. The term organism plays a special role, and the account shows why B. F. Skinner might have regarded it as an appropriate title. B. F. Skinner was an organism. So are we all, but probably few of us like to be reminded. The Copernican revolution was resisted at least in part because it eventually forced us to see our world not as the center of the universe but rather as a small planet in orbit around a minor star. The Darwinian revolution raised similarly troubling questions about our biological origins. Charles Darwin described the implications of natural selection this way: The old argument from design in Nature, as given by Paley, which formerly seemed to me so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve must have been made by an intelligent being, like the hinge of a door by man. There seems to be no more design in the variability of organic beings, and in the action of natural selection, than in the course which the wind blows, (quoted in F. Darwin, 1892/ 1958, p. 63)

Like Charles Darwin, B. F. Skinner was an inquisitive organism, and the questions they both asked are of interest to us all: Where do we come from? What makes us do what we do? What can we know about ourselves, and how do we learn it? Like Darwin's, Skinner's answers to these questions are sometimes troubling but, again like Darwin's and as I hope to show here, they are also often characterized by persuasive elegance, coherence, and parsimony. This article considers some parallels between the life and work of Charles Darwin and the life and work of B. F. Skinner. In the course of doing so, it deals with our origins by examining selection as it operates in evolution and in the shaping of behavior, and it deals with how we come to know ourselves by examining the sources of the language with which we describe our thoughts and feelings and other private events.

Darwin and Skinner Let us begin briefly with Darwin; the outlines of his biography are probably already familiar. His study is preserved, much as it was when he worked in it, at Down House in Kent, England. Darwin was born on February 12, 1809 in Shrewsbury. He attended Cambridge and traveled around the world on the Beagle. After the Darwin November 1992 • American Psychologist Copyright 1992 by the American Psychological Association, Inc. 0003-066X/92/S2.00 Vol.47, No. 11, 1521-1530

University of Maryland Baltimore County

family moved to Down House in 1842, however, he limited his travel drastically for reasons of health. For the next 40 years, until his death on April 19, 1882, Down House was the primary site of his life and work. I visited Down House more than a decade ago. At the time, I had already examined some parallels between Darwin's work and Skinner's (Catania, 1978). For me, Darwin's study was the main attraction; it included his desk and some of his books, his armchair and his writing board, and memorabilia collected during his travels or presented to him by visitors. Had it been in use, it might have seemed right to call it cluttered, but even if so it was an organized clutter. B. F. Skinner was also a scholar who did much of his writing at home, and it should be no surprise that his office and Darwin's had some common features. Skinner's office, in his home in Cambridge, Massachusetts, has been described as tiny, with a lounge chair at one end and "crowded with books, files, pictures, gadgets, hi-fi equipment" (National Public Radio, 1990). But this is a superficial comparison. It is more important that Darwin and Skinner were realists with respect to their places in the universe. Both had religious upbringings, and both lost their faith. The special property of religious belief (perhaps its defining property) is that it is held in the absence of supporting evidence, but, as Darwin put it (F. Darwin, 1892/1958): The habit of scientific research makes a man cautious in admitting evidence. For myself, I do not believe that there ever has been any revelation. As for a future life, every man must judge for himself between conflicting vague probabilities. (P. 61)

Darwin concluded a discussion of the incredibility of miracles and the "fact that many false religions have spread over large portions of the earth like wildfire" with the following (F. Darwin, 1892/1958): I found it more and more difficult, with free scope given to my imagination, to invent evidence which would suffice to convince me. Thus disbelief crept over me at a very slow rate, but was at last complete. The rate was so slow that I felt no distress. (P. 62)

Skinner, however, did not escape the distress. In "What Religion Means to Me" (Skinner, 1987), he wrote that he was rather troubled about his loss of faith for a number of vears. He also wrote I thank Barbara Ross for confirming some historical details about Skinner's last year and David Carlson for asking the right question. Correspondence concerning this article should be addressed to A. Charles Catania, Department of Psychology, University of Maryland Baltimore County, 5401 Wilkens Avenue, Baltimore, MD 21228-5398.

1521

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

Science, not religion, has taught me my most useful values, among them intellectual honesty. It is better to go without answers than to accept those that merely resolve puzzlement. I like Bertrand Russell's reply to Pascal's wager. Pascal argued that the consequences of believing in God were so immense that only a fool would not believe; but, said Russell, suppose God values intellectual honesty above all else and that He has given us shoddy evidence of His existence and is planning to damn to hell all those who believe in Him only for the sake of the glittering prizes, (p. 12)

explicit in his many references to evolutionary contingencies, and he strengthened and expanded those ties in later works (e.g., Skinner, 1966). The outlines of his new selectionist paradigm for psychology were becoming clearer; Skinner later elaborated on the operation of selection in the three realms of phylogeny, ontogeny, and culture in an article entitled "Selection by Consequences" (Skinner, 1981).

Born on March 20, 1904, B. F. Skinner grew up in the town of Susquehanna, Pennsylvania. Later, at Hamilton College, he majored in English, but he also took courses in science and philosophy. The term organism emerges in the title of one of the books he read while an undergraduate: Loeb's The Organism as a Whole (Skinner, 1976). After graduation, encouraged by a letter from Robert Frost, to whom he had sent some short stories, Skinner took a year off from academic pursuits to work at a career in writing. He gave it up on the grounds that he had nothing to say. He later referred to the time as his Dark Year. After the Dark Year, during which he gained some familiarity with the then-contemporary writings of Watson, Pavlov, and Bertrand Russell, Skinner turned from English to psychology and entered the graduate program at Harvard University. There he began a series of experiments that led to more than two dozen journal articles and that culminated in his seminal book, The Behavior ofOrganisms (Skinner, 1938, 1979). Reviews of the work at the time were mixed (cf. Catania, 1988). Some missed the point, and many commentators were still mistakenly calling Skinner a stimulus-response theorist decades later. But mixed reviews notwithstanding, The Behavior of Organisms had taken its place among the significant books of 20th-century science, and the term organism had become central. Skinner occasionally mentioned human behavior in The Behavior of Organisms (1938), but near the end of it is the following statement: "The reader will have noticed that almost no extension to human behavior is made or suggested" (p. 441). Skinner saved his case for Science and Human Behavior (1953). Probably for different reasons, Darwin had also said little about the relevance of his account to the human species in his Origin of Species (1859), but for those who did not see what was implicit there, he made the argument explicit in a later book, The Descent of Man (1871). As with Darwin, there is substantial continuity between the research that Skinner brought together in The Behavior of Organisms (1938) and his later writings, but Skinner gradually shifted from a treatment of behavior that took physics as its reference science to one that emphasized behavior as part of the subject matter of biology. The learning theories of the 1930s had attempted to formulate laws and derive principles from those laws, and like other learning theorists of the time, Skinner had included such components in his work. In Science and Human Behavior (1953), however, he made the ties to biology

Selection in phylogeny corresponds to natural selection, Darwin's account of evolution in terms of the differential survival and reproduction of the varied members of a population; the environment selects the individuals that pass on their characteristics from one generation to the next and thereby shapes the characteristics of individuals in subsequent populations (for more detailed accounts see Catania, 1992; Dawkins, 1986). Evolution by natural selection requires variations within populations; these variations are the stuff upon which selection works. Evolution has engendered controversy, but theories of evolution are not about whether contemporary species are descended from the very different ancestors that are found in the geologic record. All theories of evolution take that for granted. Rather, they differ in what they say about the way evolution came about, and the theory that has been most successful in accommodating the facts of evolution is Charles Darwin's account in terms of natural selection. Selection was well-known even before Darwin, but it was the sort used by humans in horticulture and animal husbandry. People knew how to breed plants or livestock selectively for hardiness or for yield or for other characteristics (e.g., workhorses for strength and racehorses for speed). Part of Darwin's insight was that a similar kind of selection occurred in nature, without human intervention. There was no argument with artificial selection in Darwin's day; natural selection was the problem. The evolution of the horse provides striking evidence for natural selection. Over the 50 million years or so since Eohippus, the individuals in the populations from which modern horses are descended gradually increased in size and speed. Many descendants of Eohippus must have been the fastest of their kind in their time, but they are no longer around. When selection operates on some relative property, such as speed relative to the mean for a population, the mean for the population changes. For example, after capture by predators has repeatedly selected faster escape, few descendants of the originally slow runners will be left, even if that slower running speed had provided a selective advantage at a much earlier time when it was fast relative to the population mean. In other words, as Eohippus demonstrates, examples of ancestral forms should not be expected within current populations. In this account, the source of selection is in the environment (the environments of predators include their prey, and the environments of prey include their predators). Selection both creates and maintains the features of organisms. For example, the ancestors of whales were

1522

Natural Selection

November 1992 • American Psychologist

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

once land mammals. After they moved back to the sea, the environmental contingencies that made legs advantageous no longer selected for well-formed legs. Instead, selection began to favor limbs that were effective for movement through water. The legs of the ancestors of whales gradually disappeared; in a sense the legs had extinguished or become extinct (cf. Skinner, 1988, p. 73). Selection operates on species, but it does so by acting on particular organs and systems and body parts. Natural selection along a single dimension such as running speed seems straightforward enough, but evolution involves more than changes along single dimensions. It results in organized complexity, such as the intricate structure of the human eye. Is it reasonable to believe that natural selection could have produced such organized complexity? If the eye is a product of natural selection, it could not have emerged full blown. But what good is part of an eye? What selective advantage could it confer? The answer is that even 1% of an eye is a substantial advantage if all of one's contemporaries have even less. Any sensitivity to light is better than none, 2% is better than 1%, 3% is better than 2%, and so on (cf. Dawkins, 1986). Not every feature that seems adaptive is necessarily a product of natural selection. Darwin (1859) regarded natural selection as the most important mechanism of evolution, but he took pains to point out that natural selection was not the only possible one: "I am convinced that Natural Selection has been the main but not exclusive [italics added] means of modification" (p. 6). Selectionist accounts of the features of a population demand more than just a plausible story about how those features might be advantageous. It is worth noting here that, just as Darwin never claimed that natural selection was the sole factor in evolution, Skinner never claimed that reinforcement was the exclusive means of modification for behavior, and he explicitly discussed alternative sources of behavior (e.g., Skinner, 1977). Despite clarifications, both Darwin and Skinner often had to cope with misunderstandings and misrepresentations. The Eclipse of Darwin's Natural Selection Darwin's main arguments, first published in his On the Origin of Species (1859), were warmly received in some quarters, but they were strongly resisted in others. The resistance grew over time, and by the end of the 19th century the belief was widespread that Darwinism was dead. It did not recover until well into the 20th century. The half century or so that preceded that recovery has been called the eclipse of Darwinism (Bowler, 1983; cf. Catania, 1987). The eclipse occurred not because evolution itself had been discredited but rather because theories other than Darwin's became dominant. Three of these were Lamarckism, orthogenesis, and Mendelian genetics (in the absence of mutations, Mendelian genetics could not provide the variability on which the selection of variations depended). In the 19th century, genes were theoretical entities. November 1992 • American Psychologist

Nevertheless, all of these theories assumed that hereditary material was passed on from one generation to the next and that evolution was determined by its properties. Some also assumed that the genetic material constituted a representation or copy of the organism. In the earliest versions of orthogenesis, called preformationist, embryos were literally homunculi, miniscule individuals complete in all their parts; in later variations they took on ancestral forms, as ontogeny was said to recapitulate phylogeny. As for Lamarckism, the germ plasm had to contain some kind of plan of those parts that were to be altered in subsequent generations if acquired characteristics were to be transmitted. A recipe is a sequence of procedures or instructions. It describes how to create a product, but it does not necessarily incorporate a description of it. A blueprint, on the other hand, describes a structure but does not ordinarily say how to construct it. Both can be informative, but neither is likely to include information about its origins (e.g., the number of tries it took to make the recipe or the order in which the different sections of the blueprint were designed). A blueprint is a representation or copy, but a recipe is not, and Lamarckism and the preformationist orthogenetic accounts treated genetic materials as blueprints rather than recipes. A major advance in contemporary biology was to reinterpret genetic material as a recipe for the organism's development rather than as a blueprint for its structure (a more detailed account appears in Catania, 1992; see Dawkins, 1986, for an elaboration of the metaphor of recipes and blueprints). Lamarckism and at least some varieties of orthogenesis became untenable alternatives to Darwinian selection because their implicit copy theories were inconsistent with what had been learned about how the genetic material worked. The eclipse of Darwinism ended with the modern synthesis in biology, when data from experimental genetics showed that mutation rates provided the variability upon which selection could operate. Although debate continues over the details of evolution (e.g., in the relative importance of gradual evolution versus saltation), selection remains the central paradigm of contemporary biology (cf. Dawkins, 1986). It is ironic that, along with Lamarckism and orthogenesis, Mendelian genetics had also been seen as a serious challenge to Darwinian selection. The integration of Mendelian genetics with Darwinian selection in the 1920s and 1930s, known as the modern synthesis, became the core of contemporary biology. Genetic experiments with Drosophila, the fruit fly, not only elaborated on genetic mechanisms but also brought mutations into the laboratory. With Drosophila, many generations could be studied within a relatively short time. The research gave evidence on natural rates of mutation and on the magnitude of mutation effects, which were relatively small in comparison to the changes that had been assumed in prior mutation theories. The combination of Mendelian genetics with the facts of mutation provided the variability needed for the workings of natural selection. 1523

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

Representations This is the appropriate place for one ontogenic analogy. Skinner often criticized the concept of representations in cognitive psychology, arguing that organisms do not make copies of the world (e.g., "Organisms do not store the phylogenic or ontogenic contingencies to which they are exposed; they are changed by them"; Skinner, 1988, p. 302). It is important to note that a representation sometimes implies a copy, but often does not. For example, if one is shown written letters and later recalls them, errors are more likely to be based on the acoustic than the visual similarities among the letters (Conrad, 1964). The spoken letter is in no way a copy of the visual one, because sounds have auditory rather than visual properties. The implication is that what we remember are our responses to stimuli rather than the stimuli themselves; our responses are our recipes for reproducing stimuli rather than our copies of them. The advantage of the vocabulary of recipes is that it provides an alternative to that of copies. The problem is not so much with representations that have the properties of recipes as it is with those that have the properties of blueprints (cf. Catania, 1987). It may be significant that some of the most successful cognitive accounts, such as those in terms of parallel distributed processing, do not involve representations that function as copies (cf. Donahoe & Palmer, 1989).

The Selection of Behavior "Darwinism is a theory of external control, since the internal process of variation is seen as purely random and incapable of directing evolution" (Bowler, 1983, p. 9). Just as the initiating causes of evolution lie in the environment in the Darwinian account, the initiating causes of behavior lie in the environment in the Skinnerian one. One of Skinner's earliest statements of the relation between the two types of selection was the following: In both operant conditioning and the evolutionary selection of behavioral characteristics, consequences alter future probability. Reflexes and other innate patterns of behavior evolve because they increase the chances of survival of the species. Operants grow strong because they are followed by important consequences in the life of the individual. (1953, p. 90) Behavior is a product of evolution; the selection or survival of patterns of behavior in an organism's lifetime parallels the selection or survival of individuals in evolutionary time. Both involve some variation that provides the source materials on which evolution acts, and both involve some basis for selecting what survives (parallels between these two varieties of selection, natural selection and the selection of behavior by its consequences, have been explored in considerable detail: e.g., Catania, 1987, 1992; Skinner, 1953, p. 430; Skinner, 1988, pp. 72-73; Smith, 1986). Shaping Consider an ontogenic parallel to the phylogenic selection that we considered in discussing the evolution of the modern horse. The procedure called shaping produces 1524

changes in behavior by arranging consequences for some responses but not others. For example, if only the strongest forces exerted by a hungry lever-pressing rat produce food, stronger presses will occur more often and weaker ones will occur less often, and over time the rat's presses will increase in force. Food is the consequence that selects some responses and not others. We could say that the responses that produce food survive and that the others extinguish. Let us now recall the role of artificial selection in the Darwinian account. Artificial selection was familiar in Darwin's time; what was questioned was whether such selection could operate naturally. Shaping is also an artificial selection procedure, as when an experimenter shapes the force of a rat's lever pressing or when a behavior therapist shapes the vocalizations of a nonverbal institutionalized child. In such cases, the effectiveness of shaping is self-evident. But this kind of selection is artificial, and for us, as it was for Darwin, a crucial question is whether it also operates naturally to produce some of the varied patterns of behavior that occur in everyday life. It is difficult to observe natural selection in action, even if ontogenic selection involves more manageable time spans than does phylogenic selection. After natural contingencies have done their work, only outcomes are available. For example, we can assume that ontogenic selection was involved in shaping the skill with which grizzly bears catch salmon in the rivers of the Pacific Northwest, but what we see are the differences between the inefficient performances of the young novices and the well-coordinated actions of the experienced adults. We do not see the shaping itself (the phylogenic analogy is in the incompleteness of the fossil record). Consider now the parents who always wait before attending to a crying child. They may not notice that they have gradually shaped louder and more annoying cries. The attention strengthens the crying and annoying cries are, by definition, the ones most likely to get attention. The annoying cries have survived, and other nonannoying types of behavior perhaps have extinguished. If one watches what a parent does when a child throws tantrums, it is often easy to guess how the tantrums may have arisen through the natural selection of behavior by its consequences. Shaping can be demonstrated over minutes rather than over days or years or millennia. Anyone who has mastered the art of shaping knows that 5 or 10 minutes is plenty of time for the shaping of a single response. If reinforcers can do so much to behavior when contingencies are deliberately arranged over relatively short periods of time, it is reasonable to assume that they will also affect behavior when natural contingencies operate over substantial periods throughout an organism's lifetime. The issue has been particularly controversial with respect to the acquisition of verbal behavior in children, and only limited data are available to demonstrate the role of contingencies (e.g., Moerk, 1983; Whitehurst & Valdez-Menchaca, 1988). But consider one year in the November 1992 • American Psychologist

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

life of a child. Let the child sleep, eat, and perform other functions for 16 hours of the day, and let accidental contingencies in the everyday verbal interactions between parent and child work more slowly, so that an hour or so must be allowed for each new word. That is still eight words per day, so it should be no surprise if the child has acquired several thousand words in a year. That is not too far from the vocabulary of a five-year-old child. Why is it then that some linguists claim that learning processes are irrelevant to the acquisition of vocabulary? Certainly it is reasonable to assume that children are phylogenically predisposed to master some of the properties of human language, but even if so, children could not master the languages of their native verbal communities unless their verbal environments selected appropriate vocabularies. Many contingencies may take hold of behavior over the course of months or years in the life of a young child. Some may be subtle, especially given the very broad range of events that can serve as reinforcers. Some may produce behavior that is desirable; others may do the opposite. The self-injurious behavior of an institutionalized nineyear-old child may seem resistant to change, but nine years is a very long time over which contingencies can operate. This does not mean that all such behavior is solely a product of contingencies. In the face of such possibilities, however, it is certainly more appropriate to be alert for the effects of such contingencies than to assume that they do not exist. The Eclipse of Skinner's Behavior Analysis Like Darwinism during its eclipse, Skinner's behaviorism has often been declared dead by the proponents of other approaches. Here again the parallels may be informative (although the possibilities must be particularly disquieting to those who oppose a behavior analytic account, treating it as if it were mere associationism or misrepresenting it as strict environmentalism, because they may then become the metaphorical Wilberforces of the story). If the metaphor holds and we are in the midst of an eclipse of behavior analysis, what kinds of events will lead to its reemergence? A critical feature of the Darwinian history was the development of the discipline of Mendelian genetics, its adoption of mutation theory, and its merger with selectionism in the modern synthesis. Is there an emerging discipline toward which behavior analysis should look for its synthesis? It is tempting to identify some variety of neuroscience as the critical discipline. That direction, however, seems to follow more from an associationist than from a selectionist account of behavior. Neuroscience seems not yet to have given sufficient attention to selection rather than connection as a mechanism for the production of behavior. The Darwinian problem that was resolved by the modern synthesis was the source of the variability upon which selection operated. Experimental analyses of rates and magnitudes of mutations made possible a detailed account of selection as the evolutionary process that November 1992 • American Psychologist

shaped that variability into new forms. If we look for analogous problems in behavior analysis, we should expect to find them where the most telling attacks have been directed, and that has been in the area of verbal behavior rather than in neurology. The crux of Chomsky's (1959) assault was also about creative processes: productivity in verbal behavior. Cultural Selection Through phylogenic mechanisms operating over generations, in natural selection as proposed by Darwin, the behavior of a parent can survive in the behavior of its offspring. Through ontogenic mechanisms operating over the lifetime of a single organism, in the selection of behavior by its consequences, some responses are more likely to survive than others in that organism's behavior. When the offspring can acquire behavior from the parent or from any other organism (e.g., through observation, imitation, or verbal behavior), a third arena for selection is created. This third arena completes the new selectionist paradigm for psychology. This third variety of selection, sometimes called cultural selection, occurs when behavior can be passed on from one organism to another, especially as in verbal behavior. For example, what someone has said or written can survive that person's death if it is passed on to and repeated by others (Darwin's discussion of natural selection in the evolution of human languages is completely consistent with such an account; Darwin, 1871, chap. 3). The verbal behavior that has survived within and that has been shared among the members of a group is part of the culture of that group. Behavior shared in this way need not be correlated with genetic relatedness (e.g., it is not necessary to be related to Darwin to be able to repeat some of his words appropriately). Verbal behavior may have created special problems for behavior analysis because it is a part of this different domain. It involves not only the selection of behavior by its consequences over the lifetime of an individual organism but also the transfer of behavior from one organism to another. New phenomena are already emerging from the study of this domain. These include varieties of stimulus control with novel properties (equivalence classes; e.g., Catania, Home, & Lowe, 1989; Sidman & Tailby, 1982) and properties of instruction following that can be tracked developmentally (rule-governed behavior; e.g., Catania, Lowe, & Home, 1990; Lowe, Beasty, & Bentall, 1983; Skinner, 1969). In conjunction with analyses of the structure of nonverbal behavior (e.g., Catania & Cerutti, 1986), explorations of this new domain may already be putting the question of productivity in verbal behavior to rest. But that is a different story. For present purposes, the more important point is that the questions Skinner raised about origins and about selection were not so distantly related to the questions that he raised about language. Let us now turn to Skinner's treatment of the origins of our vocabulary for speaking about ourselves. 1525

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

The Language of Private Events It is sometimes assumed that the fundamental function of verbal behavior is to communicate feelings or emotions. But the assumption is untenable because verbal communities cannot create and maintain vocabularies based solely on such events (see Catania, 1991a, for a more detailed account). The issue is not the existence of such private events as feeling or thinking or imagining. Rather, it is how we can learn to talk about them. We learn to talk about our feelings, but the words we use are taught to us by the same verbal communities that provide us with all of the other words of our language. This teaching can only be accomplished on the basis of what is publicly shared by the speakers and listeners of the language. How then can words for private events such as feelings and thoughts and ideas be taught? The core of Skinner's (1945) "Operational Analysis of Psychological Terms" is his discussion of the difficulties created by positing a language of private events that is not based on the public practices of the verbal community (useful philosophical parallels can be found in the discussion of private languages in Wittgenstein, 1958). The argument has often been misunderstood. It does not deny the private; instead, it points out the limitations imposed on the language of private events by the fact that common vocabularies can be based only on what is mutually accessible to and therefore shared by speakers and listeners. If a private feeling does not have a public correlate, how can anyone ever tell when anyone else has it? If one cannot tell, how can one ever teach the other the word for it? These difficulties are multiplied if a language of private feelings, thoughts, or ideas is assumed to provide the roots of language as well as the core of contemporary verbal practices. We usually have a more intimate relation to private than to public events, but that does not imply that we know the former in some more effective way than the latter. "The skin is not that important as a boundary. Private and public events have the same kinds of physical dimensions" (Skinner, 1963, p. 953). A parent can teach a child color names because the parent can see the colors that the child sees and therefore can respond differentially to the child's correct and incorrect color naming. (So many different consequences follow from color naming that it ordinarily does not matter whether the parent teaches the color names through explicit instruction or simply allows them to become established through casual day-to-day interactions; recall the distinction between artificial and natural selection.) With private events, the vocabulary can be taught only through extension from terms based on events to which the verbal community has access. For example, the child may learn to report pain because the parents have access to overt manifestations such as the event that caused an injury or the child's crying or facial expression; if the child has learned the names of body parts, the two kinds of verbal responses may be extended to the report of pain in a particular place (cf. Skinner, 1945). A toothache is a physical event, but the person with 1526

the toothache has access to it in a different way than does the dentist who is called on to treat it. Both respond to the unsound tooth, but one does so by feeling the tooth and the other by looking at it and probing it with instruments. Their different contact with the tooth might be compared with the different ways a seeing person and a sightless person make contact with a geometric solid, if one is trying to teach its name to the other; the seeing person does so by sight and the sightless person by touch. One kind of contact is not necessarily more reliable than the other. For example, in the phenomenon of referred pain, a bad tooth in the lower jaw may be reported as a toothache in the upper jaw. In this case, the dentist is a better judge than the patient of where the pain really is (another significant example is when a victim of a heart attack reports pain in the shoulder or in the small of the back rather than within the chest). We often think of private events such as our feelings and our thoughts as ones to which we have privileged access and therefore of which we have special knowledge. But we learned the relevant words from others, and all they had access to in teaching them to us were the public correlates. If we can be mistaken even about the location of a toothache, what assurance do we have that any of our other reports of private events are reliable? Some verbal responses that superficially seem to report private events may instead be determined primarily by the situation within which behavior occurs. For example, if you suddenly find yourself eating voraciously, you may say "I must have been very hungry." This is not a report of a private state; rather, you are saying of yourself what you would have said of another if you had observed that kind of eating in someone else. Just as we judge others on the basis of observations of their behavior, we judge ourselves on the basis of observations of our own behavior (e.g., Bern, 1967). Most processes called cognitive (e.g., imagining or visualizing) are private events. We cannot see what someone else is imagining, but imagining, like walking or talking, is something we do. Some might argue that these private events should not be called behavior. Yet behavior is not limited to movements. It is plausible to assume that imagining shares something with the behavior of looking at things (we can discriminate our imagining from our seeing; when we fail to do so, we are said to have hallucinations; cf. Skinner, 1953). Our imagining is not limited to the visual mode. We not only visualize; we hold imaginary conversations, we take imaginary journeys, and we perform imaginary actions. These are analogous to computer simulations, imitations in the absence of relevant stimulation of some parts of the behavior that might occur in various situations. Just as simulation games may demonstrate potential consequences of different strategies, so our imaginings may bring us into contact with the potential consequences of our actions. But just as simulations may fail because they do not incorporate all of the relevant variables, our imaginings may fail because they involve not real contingencies but only our own incomplete re-creations of them. November 1992 • American Psychologist

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

These examples show how a behavioral account may be brought to bear on phenomena that are traditionally regarded as cognitive. The analysis of private events must deal with the problem of establishing a private vocabulary. Some private events may not even be reportable. If that is the case, it may be possible to study them by indirect means (e.g., as when shifts of attention are studied by measuring their latencies; cf. Catania, 1992, chap. 15). It follows from Skinner's (1945) analysis of the language of private events that the problem of verbal origins extends to all psychological terms. For any such term, one essential question is how it could have been learned; another is how it could be taught. This may be reminiscent of the rhetorical debating tactic of challenging the definitions of terms, but it has the advantage that the argument always returns to the verbal environment and the practices of the verbal community. Once Skinner had grappled with the origins of the terms with which he described his own behavior, it was a small step for him to move on to considering his own behavior as a scientist. One significant consequence of extending the analysis of selective contingencies to cases in which behavior passes from one organism to another, as in verbal behavior, is that the science of behavior can be turned on those scientific practices themselves. The conditions under which scientific vocabularies are established and maintained became part of the subject matter of a functional analysis of verbal behavior (Skinner, 1957). Such an analysis proceeds not in terms of grammatical or linguistic structures but rather in terms of the antecedents and consequences of behaving verbally (the most important antecedents and consequences of verbal behavior are social ones; cf. Catania, 1992). The questions of origins and knowledge and language are complexly interrelated, perhaps in an intellectual clutter, but even if so, an organized one.

formerly excited in me, and which was intimately connected with a belief in God, did not essentially differ from that which is often called the sense of sublimity; and however difficult it may be to explain the genesis of this sense, it can hardly be advanced as an argument for the existence of God. (p. 65)

Life and Death

I'm not religious, so I don't worry about what will happen after I am dead. And when I was told that I had this and would be dead in a few months, I didn't have any emotion of any kind at all. Not a bit of panic, or fear, or anxiety. Nothing at all. The only thing that touched me was, and really, my eyes watered when I thought of this, I will have to tell my wife and my daughters. You see, when you die you hurt people, if they love you. And you can't help it. You've got to do it. And that bothered me. But otherwise, my dying, I knew I was going to die. Now I know about when. I've had a very good life. It would be very foolish of me to complain, in any way, about it. So I'm enjoying these last few months as well as I ever enjoyed life.

We have considered Skinner's views on selection, behavior, and language. In doing so, we have merely sampled a few features of his responses to our most fundamental questions about where we came from, what we are, and how we come to know ourselves. Skinner's life and his death were consistent with the answers he proposed. The comparison with Darwin remains appropriate. It is not difficult to imagine how Skinner might have responded to the following account by Darwin of his convictions and feelings (F. Darwin, 1892/1958): The most usual argument for the existence of an intelligent God is drawn from the deep inward conviction and feelings which are experienced by most persons. Formerly I was led by feelings such as those just referred to . . . , to the firm conviction of the existence of God and the immortality of the soul. . . . I well remember my conviction that there is more in man than the mere breath of his body; but now the grandest scenes would not cause any such convictions and feelings to rise in my mind. . . . I cannot see that such inward convictions and feelings are of any weight as evidence of what really exists. The state of mind which grand scenes

November 1992 • American Psychologist

It is relevant to ask how Darwin learned to speak of convictions, feelings, soul, and God. His judgments still command respect because the evidence mattered so much to him (F. Darwin, 1892/1958): As far as I can judge, I am not apt to follow blindly the lead of other men. I have steadily endeavored to keep my mind free so as to give up any hypothesis, however much beloved (and I cannot resist forming one on every subject), as soon as facts are shown to be opposed to it. (pp. 55-56) Skinner (1987) too accepted facts: I accept the fact that like all living things I shall soon cease to exist. For a time, some of the genes I have carried will be replicated in my children, and something of me will survive in the books I have written and in the help I have given other people. Death does not trouble me. I have no fear of supernatural punishments, of course, nor could I enjoy an eternal life in which there would be nothing left for me to do, the task of living having been accomplished, (p. 13)

Skinner wrote this passage before he knew of his leukemia. He had also written about death and the fear of death in Enjoy Old Age (Skinner & Vaughan, 1983). But, like Darwin, who near the end said "I am not the least afraid to die" (F. Darwin, 1892/1958, p. 348), the imminence of his own death did not change what he had to say about mortality. Skinner learned of his leukemia on November 10, 1989, when he had a bone marrow test after hospitalization for an attack of angina. At the time, he was told he had two months to live. This is how he described his reactions in an interview (National Public Radio, 1990):

The first hint of Skinner's leukemia came to me during the last month or so of 1989, when a colleague asked during a phone conversation if I knew anything about Skinner's illness and wondered whether the leukemia was only a rumor. I had been corresponding with Skinner about a manuscript I had submitted to the American Psychologist (Catania, 1991b), and I received firm information in a letter from Skinner, dated January 15, 1990, that included the following: The leukemia is something of a nuisance. I have to go over once 1527

a week or so for transfusions and whatnot and have recently had a vascular access catheter put in on my chest to avoid getting needles into large veins on each occasion. I'm feeling fine and enjoying life, though I'm not getting as much done as I once did.' More followed in a letter dated February 10, 1990:

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

The leukemia is under control in one sense: so long as I have transfusions of platelets and red cells, I feel perfectly normal. However, my white count is going way up and that means that my resistance to disease is declining. Although I will feel fine up to the end, something or other will take me off in a hurry, so I'm told. I've had a good life and this doesn't bother me too much. Letters to other colleagues during that time included variations on the information. For example, a letter to Joseph V. Brady (1990) included the following paragraph: I don't know whether you've heard about my leukemia. So long as I get platelets and red cells, I feel perfectly normal. But of course, in the not too distant future, some silly infection will take me off. I've had a good life, and it would be rather ungracious to complain, don't you think? Skinner elaborated on the circumstances in an interview (National Public Radio, 1990): It's very curious, is leukemia. I recommend it as a terminal illness, because if you get blood then you're perfectly normal, except that the white cells deteriorate, and eventually you are extremely vulnerable to infection, and that's why my wife may have asked you to wash your hands or something, I don't know. It's silly, because the doctor tells me probably what you will die of is something you already have in you, but it will suddenly have a field day and it'll be the end. Something like pneumonia or something. But until that last couple of days you are perfectly healthy. The last letter I received from him was dated July 12, 1990. It included brief comments on material I had sent to him, and the following: "The critical episode in the leukemia a couple of weeks ago has put me back. . . . Wish I had time for more but that's that." On August 10, 1990, Skinner accepted an award from the American Psychological Association for a lifetime of achievement in psychology. It was his final public appearance. On August 17, 1990, while in the hospital, he put the finishing touches on his last paper (Skinner, 1990a) and had it sent off to the American Psychologist. He died on August 18, 1990. "Near the end, his mouth was dry. Upon receiving a drink of water he said his last word, 'Marvelous' " (Vargas, 1991, p. 2). Some time before his death Skinner had assembled transcripts of letters he had written to one of his Hamilton College professors, A. P. Saunders, during his Dark Year (Skinner, 1990b).2 On his instructions, copies were sent out to some of his friends and colleagues, and a few days 1 Letters from B. F. Skinner to A. Charles Catania are in the private collection of the author. 2 The 1926 letter from B. F. Skinner to A. P. Saunders is excerpted from Skinner (1990b) with the permission of the B. F. Skinner Foundation.

1528

after his death I received the set. On the cover he had written Dear Charlie Hope these amuse you. Fred. Skinner had tutored one of the children in the Saunders family, and, as he put it in the Preface, "For three of my college years, then, I was a familiar of the Saunders household.. . . These letters to Dr. Saunders are probably the best record of my life at that time" (Skinner, 1990b). The one most relevant here is dated August 16, 1926. It began Dear Dr. Saunders, This letter isn't important. Put off reading it until some evening when a cigar and a fire in the music room will seem agreeable. The main thing about this letter is my writing i t . . . . He gave a brief account of the problems of writing objectively and then continued, "But let that all go—there is the bigger question of life itself." The following passage describes Skinner's experience of the death of his grandfather (the word organism appears in the description; I was so struck by the word when I first read it here that it gave me the title of this article, but I have resisted the temptation to italicize it): Just before commencement (June 1) my grandfather Burrhus was operated upon by my friend the doctor for enlarged prostate. Two weeks later he was again operated on for hydrocele. Despite his age (77) he recovered rapidly and about the first of July came to our home to convalesce. While he was here I attended to all his dressings—which were numerous—and we got to know each other well. He was having some trouble with his son—my uncle—and he confided completely in me and gave me the credit for straightening the affair out. He would let no one else do anything for him but me. After he was home here a week he took cold, went out of his head in a day or so and 3 days later died of bronchial pneumonia. For a day and a half I watched him—he was apparently awake yet unconscious save for neuralgic pains—he hiccoughed badly—until the last evening they gave him morphia. This depressed his lungs which brought on coughing and his right lung filled completely within an hour. Then all night long this organism—worn out, beyond repair lay there. Certain muscles of his diaphragm went on functioning— a little air was pulled spasmodically into the remaining lung space. An overtaxed heart—sustained on strychnine—pumped impure blood—and gave out under the strain. His pulse weakened—he coughed a bit and lay still. I listened to his heart—it was still. I lifted him up—a little black fluid ran from his lips—. I watched this human organism wear out—watched it as unemotionally as possible—and tried to understand it. What had happened. The active idea which I had known as my grandfather was gone simply because certain physical properties of his body had given out. Was there anything more of him beside that, something spiritual? If so when did it leave him? At the last moment?—except for certain reflex muscular activities the minute before and the minute after were alike. I am very sure that my grandfather—all of him—all that I knew of him and felt—his character, personality, emotions, skill, desires,—all—everything went as soon as the physical condition of his body became unfit for certain nervous coordiNovember 1992 • American Psychologist

nations. Just as the dreary character of the clock I now hear will vanish when the parts which give forth its ticking shall stop. Later in the letter, Skinner wrote "Call this letter morbid if you like. Call it anything. I'm trying to be honest—I could feel better about life if I'd close my eyes. But. . . wide open—nothing—."

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

Organisms Many humans are as reluctant to call themselves animals as they are to call themselves machines (in fact, computer metaphors of mind suggest that, given the choice, machines are preferable; perhaps that is because machines are more easily repaired). The distinction is maintained even in technical works, as when textbooks in psychology distinguish between animal learning and human learning. To be called an animal is not ordinarily taken as a compliment. A special relationship must exist before one can refer to a friend or colleague in that way without insult. After Thomas Huxley gave an address on the hypothesis that animals are automata, the animal component remained implicit when Charles Darwin wrote the following to him: "Once again, accept my cordial thanks, my dear old friend. I wish to God there were more automata in the world like you" (F. Darwin, 1892/1958, p. 347). To speak of humans as organisms is still in many quarters an unpopular step, but for Skinner it was crucial. Although The Behavior ofOrganisms (1938) dealt mainly with the behavior of the white rat, the usage is evidence of Skinner's conviction that his work was relevant to human behavior. If we are organisms, then knowing that is simply part of knowing ourselves. Like Darwin's, Skinner's message has, on the whole, not been well received. An example: During a lecture on the origins of the language of private events, I once asked whether the class had gotten the point and one student replied "Oh, I got it; I just don't like it" (the question made me realize how important it is explicitly to teach students the difference between getting a point and liking it). The way the bearer of news is treated often depends more on whether the news is regarded as good or bad than on whether it is correct and complete. This property of behavior, too, is consistent with behavioral analyses. Despite the role that is frequently attributed to the processing of information, organisms do not work to produce information per se; they work to produce good news, but they do not work to produce bad news (in other words, information is not a reinforcer; see, especially, Dinsmoor, 1983). We have completed this brief survey of the life and work of B. F. Skinner. As with any comparison, the analogy with the life and work of Charles Darwin holds only up to a point. It would be interesting to know how the analogy will look a century from now. Meanwhile, the life and work of B. F. Skinner could justify many different titles. He could have here been called B. F. Skinner, psychologist, or B. F. Skinner, Utopian, or B. F. Skinner, scientist, or B. F. Skinner, humanist, or B. F. Skinner, philosopher, or B. F. Skinner, behaviorist, or B. F. Skinner, November 1992 • American Psychologist

poet, to list just a few possibilities. Why then not even B. F. Skinner, human, but rather B. F. Skinner, organism? Skinner's interest in etymology (Skinner, 1989) would have made him familiar with the origins of the title offered here. Organ came first, from a Greek root meaning work, as the instrument or machine that was the source of church music in the Middle Ages (though technically not yet the contemporary church organ). By the 17th century, it was also well-established as an instrument of thought or knowledge, as in Bacon's "Novum Organum" (note also that Skinner often contrasted his Baconian views with Cartesian ones). The sense of instrument was then transferred by metaphorical extension to the working stuff of living creatures. In contemporary definitions, organism means a living animal or vegetable or, somewhat tautologically, that which has an organic structure. For Darwin, in a glossary that accompanies some editions of his On the Origin of Species (1859), an organism was "an organised being, whether plant or animal." In these definitions there is often the implicit sense of an organized body consisting of connected and mutually dependent interactive parts. We have seen how often the term figured in Skinner's thinking. He also spoke of the self as an organized system of responses, and of the individual as a locus in which many variables come together to produce an outcome (Skinner, 1953, 1972). That is the sense in which we may grant him his title as particularly fitting: In one of its definitions, an organism is that which behaves as a unified whole. REFERENCES Bern, D. J. (1967). Self-perception: An alternative interpretation of cognitive phenomena. Psychological Review, 74, 183-200. Bowler, P. J. (1983). The eclipse of Darwinism. Baltimore: Johns Hopkins University Press. Brady, J. V. (1990). "It would be rather ungracious to complain." Division 25 Recorder, 26, pp. 1, 4. Catania, A. C. (1978). The psychology of learning: Some lessons from the Darwinian revolution. Annals ofthe New York Academy ofSciences, 309, 18-28. Catania, A. C. (1987). Some Darwinian lessons for behavior analysis: A review of Peter J. Bowler's The eclipse of Darwinism. Journal of the Experimental Analysis of Behavior, 47, 249-257. Catania, A. C. (1988). The behavior of organisms as work in progress. Journal of the Experimental Analysis of Behavior, 50, 277-281. Catania, A. C. (1991 a). The phylogeny and ontogeny of language function. In N. A. Krasnegor, D. M. Rumbaugh, R. L. Schiefelbusch, & M. Studdert-Kennedy (Eds.), Biological and behavioral determinants of language development (pp. 263-285). Hillsdale, NJ: Erlbaum. Catania, A. C. (1991b). The gifts of culture and of eloquence: An open letter to Michael J. Mahoney in reply to his article, "Scientific psychology and radical behaviorism." Behavior Analyst, 14, 61-72. Catania, A. C. (1992). Learning (3rd ed.). Englewood Cliffs, NJ: Prentice Hall. Catania, A. C , & Cerutti, D. (1986). Some nonverbal properties of verbal behavior. In T. Thompson & M. D. Zeiler (Eds.), Analysis and integration of behavioral units (pp. 185-211). Hillsdale, NJ: Erlbaum. Catania, A. C , Home, P., & Lowe, C. F. (1989). Transfer of function across members of an equivalence class. The Analysis of Verbal Behavior, 7, 99-110. Catania, A. C , Lowe, C. E, & Home, P. (1990). Nonverbal behavior correlated with the shaped verbal behavior of children. Analysis of Verbal Behavior, 8, 43-55.

1529

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

Chomsky, N. (1959). Review of B. F. Skinner's Verbal behavior. Language, 35, 26-58. Conrad, R. (1964). Acoustic confusions in immediate memory. Journal of Experimental Psychology, 92, 149-154. Darwin, C. (1859). On the origin of species. London: John Murray. Darwin, C. (1871). The descent of man. London: John Murray. Darwin, F. (Ed.). (1958). The autobiography of Charles Darwin and selected letters. New York: Dover. (Original work published 1892) Dawkins, R. (1986). The blind watchmaker. New York: Norton. Dinsmoor, J. A. (1983). Observing and conditioned reinforcement. Behavioral and Brain Sciences, 6, 693-728. Donahoe, J. W., & Palmer, D. C. (1989). The interpretation of complex human behavior: Some reactions to Parallel distributed processing. Journal of the Experimental Analysis of Behavior, 51, 399-416. Lowe, C. F., Beasty, A., & Bentall, R. P. (1983). The role of verbal behavior in human learning. Journal of the Experimental Analysis of Behavior, 39, 157-164. Moerk, E. L. (1983). A behavioral analysis of controversial topics in first language acquisition: Reinforcements, corrections, modeling, input frequencies, and the three-term contingency pattern. Journal ofPsycholinguistic Research, 12, 129-155. National Public Radio. (1990). "All things considered" [Interview with B. F. Skinner, July 27, 1990]. Division 25 Recorder, 24/25, 34-36. Sidman, M., & Tailby, W. (1982). Conditioned discrimination versus matching to sample: An expansion of the testing paradigm. Journal of the Experimental Analysis of Behavior, 37, 5-22. Skinner, B. F. (1938). The behavior of organisms. New York: AppletonCentury-Crofts. Skinner, B. F. (1945). The operational analysis of psychological terms. Psychological Review, 42, 270-277. Skinner, B. F. (195 3). Science and human behavior. New York: Macmillan. Skinner, B. F. (1957). Verbal behavior. New York: Appleton-CenturyCrofts. Skinner, B. F. (1963). Behaviorism at fifty. Science, 140, 951-958. Skinner, B. F. (1966). The phylogeny and ontogeny of behavior. Science, 153, 1205-1213.

1530

Skinner, B. F. (1969). An operant analysis of problem solving. In B. F. Skinner, Contingencies of reinforcement (pp. 133-157). New York: Appleton-Century-Crofts. Skinner, B. F. (1972). A lecture on "having" a poem. In B. F. Skinner, Cumulative record(3rd ed., pp. 345-355). New York: Appleton-Century-Crofts. Skinner, B. F. (1976). Particulars of my life. New York: Knopf. Skinner, B. F. (1977). Herrnstein and the evolution of behaviorism. American Psychologist, 32, 1006-1012. Skinner, B. F. (1979). The shaping of a behaviorist. New York: Knopf. Skinner, B. F. (1981). Selection by consequences. Science, 213, 501504. Skinner, B. F. (1987, Spring). What religion means to me. Free Inquiry, 7(2), 12-13. Skinner, B. F. (1988). Replies to commentators. In A. C. Catania & S. Hamad (Eds.), The selection of behavior. New York: Cambridge University Press. Skinner, B. F. (1989). The origins of cognitive thought. American Psychologist, 44, 13-18. Skinner, B. F. (1990a). Can psychology be a science of mind? American Psychologist, 45, 1206-1210. Skinner, B. F. (1990b). Letters to Professor A. P. Sounders from B. F. Skinner, during the Dark Year. Unpublished manuscript. Skinner, B. F, & Vaughan, M. E. (1983). Enjoy old age. New York: Norton. Smith, T. L. (1986). Biology as allegory: A review of Elliott Sober's The nature of selection. Journal of the Experimental Analysis of Behavior, 46, 105-112. Vargas, J. S. (1991). B. F. Skinner—The last few days. Journal of the Experimental Analysis of Behavior, 55, 1-2. Whitehurst, G. J., & Valdez-Menchaca, M. C. (1988). What is the role of reinforcement in early language acquisition? Child Development, 59, 430-440. Wittgenstein, L. (1958). Philosophical investigations (3rd ed.). New York: Macmillan.

November 1992 • American Psychologist