The Continued Evolution of Creative Darwinism

The Continued Evolution of Creative DarwinismAuthor(s): Dean Keith SimontonSource: Psychological Inquiry, Vol. 10, No. 4 (1999), pp. 362-367Published by: Taylor & Francis, Ltd.Stable URL: http://www.jstor.org/stable/1449466 .

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Psychological Inquiry Copyright C 1999 by 1999, Vol. 10, No. 4, 362-367 Lawrence Erlbaum Associates, Inc.

AUTHOR'S RESPONSE

The Continued Evolution of Creative Darwinism

Dean Keith Simonton Department of Psychology

University of California, Davis

The commentators represent pretty much the gamut of viewpoints about my basic thesis. Their remarks range from the sympathetic to the dismissive, with a few occupying more conciliatory but still critical positions. After reading them all, I came to realize how much I placed myself in an uncomfortably untenable position in writing the target article. The article had been written simultaneously with a book-length treat- ment of the same subject (Simonton, 1999). In some respects, the article may be seen as an abstract of that larger monograph. Obviously, the book could go into much greater detail with respect to both theory and research. To offer a dramatic illustration, the text of the target article has half as many words as found in the book's second chapter, which is exclusively devoted to the creative process. There then follows a succession of sizable chapters devoted to individual differences in intellect and personality, creative development, creative products and career trajectories, and the sociocultural context. Hence, perhaps the best response to some of the commentaries would be simply: Read the book, revise your comments accordingly, and then I will compose my reply. But that option is not open to me. So I must respond to the diverse reactions as if the book were still in the future.

Hence, making the best out of a bad situation, I respond to those issues that can be addressed in the lim- ited space allotted to a reply. These issues concern expertise, randomness, religion, and evolution.

Expertise

Several commentators, including Ericsson, Russ, and Mumford, apparently believe that Darwinian models place too little emphasis on expertise, as defined by accumulated training, practice, and experience. This belief is probably misplaced. Advocates of Darwinian theories of creativity, whether James, Skinner, Camp- bell, Eysenck, or myself, all agree that evolution entails the accumulation of adaptations. Moreover, these adaptations have a major part to play in the generation

of the novel variations that enter into the selection process. It could not be otherwise. After all, why should Darwinian models shortchange the creative process when organic evolution itself, the very inspiration for these models, incorporates the accumulated experience of a species at the very source of its own variation mechanisms? This was a point made in the target article, but evidently I was not sufficiently emphatic. Con- trary to what Russ affirmed, variations in organic evolution are by no means completely random. In- stead, the variations show considerable wisdom, a biological expertise predicated on the entire evolutionary history of the species. This received evolutionary expertise manifests itself in the differential mutation rates across chromosomal sites and environmental conditions, the constraints imposed by chromosomal linkage, the emergence of dominant versus recessive genes, the relative importance of sexual versus asexual reproduction, and, most critically, the comparative gene frequencies that make up the population. As a consequence, not only are some genetic combinations more common than others, but even some mutations are more common than others as well. So prominent are these factors that many species can survive for mil- lions of years without any appreciable alteration in their principal morphological and physiological features. An evolutionary model of human creativity cer- tainly should feature no less experiential influence on its variation processes.

Yet, as Gardner and Martindale point out, creativity takes many forms, and these forms vary greatly in the degree to which accumulated expertise can be effec- tively utilized. At one extreme are "small-c" levels of creativity where the individual needs do little more than adapt previously useful solutions to a recogniz- able variation on a well-known and well-defined problem. At the other extreme are most "big-C" levels of creativity, such as the unanticipated breakthroughs that underlie major artistic and scientific revolutions. At this end of the continuum a point is usually reached where acquired expertise does not lead to the required solution, requiring that the creator rely on some form



AUTHOR'S RESPONSE

of unguided variation. In other words, the more "unprecedented" the idea, the more Darwinian the proce- dure. An undeniable example was the process that led to the discovery of DNA (see Watson, 1968). Not only was considerable trial and error required in divining the general structure of the molecule-the great scientist Linus Pauling missed it altogether-but even once the correct double helix form was hypothesized, the specific molecular structure was only determined by an explicitly and overtly trial-and-error method. James Watson actually sat down with cardboard models of the bases and literally tinkered around until he got the right match, like a kid playing with the pieces of "the world's most difficult puzzle." Expertise could tell Watson what purine and pyrimidine molecules made up DNA but not how they interlocked to form the genetic code-the keystone discovery that revolution- ized the biological sciences.

This distinction between different magnitudes of creativity is also important in addressing one of Mumford's criticisms. I had argued that one reason why it is difficult for a creator to acquire a reliable expertise is that the environmental feedback is much less consistent and stable in the case of creative achieve- ments. Mumford provided counterexamples, including Amabile's (1982) consensual assessment technique. But these instances all entail relatively low levels of creative activity (and often conflate creativity with technical competence besides). To the extent that the creativity is written in capital letters, the feedback becomes far more inconsistent and unstable. As noted in footnote 9 of the target article, the contradictory nature of the feedback even holds for the sciences. Indeed, who among us needs to have this pointed out? Who hasn't received totally contradictory comments from those who evaluated our manuscripts or grant propos- als? Aren't those of us who have written target articles familiar with commentaries that go all over the map with respect to positive and negative remarks? So the best response to Mumford may be simply to have him read all of the commentaries on the target article. Let him imagine, as well, what the response would be if my article had presented a totally revolutionary theory rather than something that represents no more than "normal science."

One last point about expertise: As Stemnberg pointed out, accumulated knowledge and skill can actually interfere with creativity. I have shown how this can happen in a recent study of the careers of 59 opera composers (Simonton, in press). One might think that the more operas a composer writes in a particular genre, the better his or her operas get, but that turns out not to be the case. The composer is actually better served writing operas in several different genres. Better yet is to create a lot of compositions that are not operatic at all, such as symphonies, quartets, and sona- tas. It is as if a track coach told his or her athletes that

the best way to prepare for the Olympics is to practice gymnastics. In creative domains, the negative effects of "over-training" are as conspicuous as the positive effects of "cross-training." Only the latter encourages creators to look at problems in new and often totally unanticipated ways (for an excellent illustration, see Poincare, 1921).'

Randomness

I must begin by disagreeing with what Russ said about Poincare's (1921) conception of the creative process. Poincare made it quite clear that the uncon- strained permutation of ideas has a major part to play in creativity. He specifically used the metaphor of the ki- netic theory of gases to describe how ideas collide and bounce off each other until certain stable combinations emerge (what in 1988 I styled "chance configura- tions"). In fact, it was actually Poincare's graphic description of the creative process that first inspired me to propose a mathematical model that predicts both individual differences and longitudinal changes in creative productivity and career landmarks (Simonton, 1991, 1997).2 The differential equations that yield the prediction equations derived directly from the random nature of this process. In fact, they are virtually identi- cal to the equations for chemical reactions that are sup- posed to act in the same manner Poincare described.

However, when Poincare compared the creative process to the random collision of atoms until stable molecules appeared, he was not saying that creativity lacked any guidance whatsoever. He explicitly stated that only certain atoms were placed in the hopper, namely those that were set loose during the preparation period. These included ideas that were explicitly thought relevant to the problem at hand, or at least were closely related to that problem (i.e., tossed in by "spreading activation," to use modem terms). Hence, the atoms in Poincare's mental chamber included certain relevant mathematical concepts or images, not what he had for dinner, a bill that had to be paid, or a new shirt that he had purchased. In short, as noted earlier, the ideational variations are usually constrained to mental elements that are most likely to be relevant rather than randomly combining all possible concepts willy-nilly. Even then, Poincare indicated that some- times atoms will be thrown into the chaotic mixture

Another peculiarity that is often seen in actual creative products is the phenomenon of the unsuccessful revision. These are instances where creators revise one of their earlier works, only to make them less effective (e.g., the successive editions of Darwin's own Origins ofSpecies). One would think that accumulated expertise would make revisions uniformly superior to the originals.

It may be pertinent to point out that the 1997 Psychological Re- view article that developed this model was honored with the 1997 George A. Miller Outstanding Article Award.

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that would not have been deemed germane during the preparation period but rather represent haphazard in- trusions ("cross-talk" or "hybridization") from seem- ingly different mathematical problems. Albeit more rarely, these irrelevancies will occasionally produce a totally unexpected synthesis of hitherto disparate domains (cf. the "bisociations" of Koestler, 1964).

Judging from Russ's remark and those of other critical commentators, such as Schooler, I believe there is much confusion about both "blindness" and "randomness." The first thing to note is that blindness is not equivalent to randomness. All random processes are blind, but not all blind processes are random. Campbell (1960) cited the systematic sweep of radar as a proce- dure that is blind but not random (and this example was repeated in my article). Moreover, it is essential to no- tice that there are degrees of blindness (i.e., it is a con- tinuous quantity rather than a qualitative or discrete attribute). Radar sweeps usually focus on specific portions of the airspace. The more such constraints are imposed on the search, the more foresight in the blindness.

This same continuity applies to the concept of randomness (see Simonton, 1999, for details). Only when all alternative outcomes have exactly equal probabili- ties is the process is said to be completely random. This situation would hold for an ideal die toss or coin flip. More common is quasi-randomness. Some alternatives are more probable than others, but not to the degree that the outcome is predictable or determined. To the extent that the outcome is unpredictable is the extent to which it can be ascribed to chance, and thus called quasi-random. Total equiprobability is not a prerequi- site for a Darwinian theory of creativity (nor is it for organic evolution, as already observed). Hence, many cognitive processes can operate so as to produce quasi-random (and thus partially blind) variations even if the processes are themselves not totally random. Take Schooler's discussion of spreading activation, for example. As this process permeates the most remote recesses of the semantic network, it becomes increas- ingly unclear what specific concepts will be primed. This is especially true because the linkages between concepts may take many forms, including those that ig- nore the logical or denotative relations between ideas (as in the tip-of-the-tongue phenomenon). Indeed, as Russ noted in her commentary, some of the associations may be driven by affective connotations. The latter, I would argue, often link concepts in ways that do not always have a strong a priori linkage with the given problem (e.g., scientific concepts that evoke the same emotional associations according to the idiosyncratic experiences of a particular scientist). The extreme rich- ness by which our ideas can be connected means that the outcome should be quasi-random, in the sense of being unpredictable. This unpredictability is aug- mented all the more by the chaotic influx of external

stimuli that are constantly priming different portions of our associative network (as pointed out by Schooler). Nothing more is required of a Darwinian model given that the variations in organic evolution are also only quasi-random.

Near the end of the target article I made a comment that was either misinterpreted (Stemnberg) or over- looked (Mumford). I argued that the human mind is in- credibly complex, with many different mental operations and processes that can be brought to bear on any given problem. In mundane problems, the response will be so automatic that the solution can be said to be algorithmic. But as problems become more novel and subtle, the number of potential approaches becomes very large and the various alternatives in- creasingly more equiprobable. Hence, even if every single one of these mental procedures entails no chance or blindness whatsoever, the net result may be said to involve that very quality. In other words, the creative process may be Darwinian even if not a single component of that overall process is random. The whole may be different from the sum of its parts. This almost chaotic complexity would be especially pro- nounced in those individuals who have extremely flat association gradients (including numerous cross-modal and affective connections) and who are extremely open to extraneous influences (e.g., defocused attention, as discussed by Martindale). Fur- thermore, to the extent that one or more component processes do indeed function in a quasi-random fashion, the aggregate behavior of the entire creative mind should become all the more unpredictable.

Religion

As noted earlier, the feedback we get from our colleagues is seldom consistent. One illustration of this in- consistency may be found in the rather different take that Feist and Stemnberg have on the Darwinian model. The former evaluated the model in terms of its scientific value and argued that it represents pretty good science, with only a few qualifications. Stemnberg, on the other hand, took the position that such evolutionary models represent a religious faith rather than a scientific theory. Stemnberg's remarks did not come as a sur- prise to me. As editor of the Journal of Creative Behavior, I had put together a special issue devoted to the evaluation of Campbell's (1960) model. Where Perkins (1998) contributed a very balanced evaluation (as he does in his commentary here), Stemnberg (1998) offered an extremely critical attack. It looks like it will always be one of those issues about which he and I must agree to disagree. Nonetheless, I would like to respond to at least some of his arguments. Consider the following four criticisms (see Cziko, 1998, for other arguments against Steinberg's views):

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1. Stemnberg claimed that creativity is "for- ward-looking and intentional" whereas evolution is not, and that undermines the plausibility of a Darwinian model. As I tried to indicate in the target article, and as I discuss in more depth in my book, I agree that human creativity is purposive,3 but I do not concur with the conclusion that a creator's desire to solve extremely important problems gives him or her the ability to do so, even when he or she has already demonstrated that he or she has the necessary expertise. Newton really wanted to solve the three-body problem (i.e., lunar theory), and no scientist of his day had more capacity than he to pull it off, but he failed. Einstein had the strongest possible desire to construct a unified field theory that would rel- egate quantum theory to the rubbish can, and spent most of his career trying to do so, to utter disappoint- ment and failure. Examples like these can be given over and over, for the arts as well as the sciences. Where there is a will, there is not necessarily a way-especially when the creative individual has taken on a problem of unprecedented magnitude and significance.

2. Stemnberg argued that the evolution of organ- isms never ends, whereas the affirmation of a Dar- winian theory of creativity implies the "end of history" and the "end of science." This curious criticism falters on two counts. First, in a sense, organic evolution has indeed ended in that no new major life forms (i.e., phyla or even families) have emerged for mil- lions of years. In the animal kingdom, for example, evolution is now confined to fine-tuning the basic morphological and physiological features of the ver- tebrates, arthropods, mollusks, echinoderms, and other successful phyla. Second, once Charles Darwin offered his theory of the evolution of species by natural selection, that was by no means the end of matters in the biological sciences either-especially after Darwinism merged with genetics to produce the Modem Synthesis (Neo-Darwinism) but theory and research continued to generate new models and data (as in the recent debate about punctuated equilib- rium). By the same token, even if I succeeded in con- vincing my colleagues that creativity was fundamen- tally Darwinian, that persuasive victory would not indicate that all future developments are foreclosed. On the contrary, such a theory should suggest a whole array of future theoretical and empirical inqui- ries. It would be a beginning, not a termination.

3. Stemnberg said that a Darwinian theory cannot account for individual differences in creativity, but this assertion is plain wrong. In fact, the theory can account for several specific features that no other theory can, so far, accommodate in its entirety, such as the distinctive cross-sectional (lognormal) distribution, the substan- tial individual differences in career trajectories (including the highly constrained relations among the first, best, and last contributions), and the cross-sectional form of the equal-odds rule (Simonton, 1991, 1997). The latter is perhaps the most provoca- tive, because the theory predicts that output quality is a positive linear function of total quantity. As a result, those creators who are the most prolific in the generation of successful ideas will also tend to be the most prolific in the generation of unsuccessful ideas. This prediction has been verified in many studies. For instance, the mean citation rate of a researcher's articles is approximately the same no matter whether the researcher publishes a lot or a little (see, e.g., White & White, 1978). When this cross-sectional equal-odds rule is coupled with its longitudinal form (i.e., the hit rate does not improve over the course of a career), it seems difficult to argue that creative individuals acquire some special expertise that allows them to side- step the trial-and-error process.

4. Stemnberg asserted that many of the explanations provided by the Darwinian model are merely "just-so stories," especially since other theoretical positions, and even common sense, can often explicate the phenomenon equally well. That observation alone tells us nothing. There also exists a 99% explanatory overlap between classical physics (Newtonian and Maxwellian) and modem physics (relativity and quantum theories). Indeed, at the level of everyday experience-or even what can be demonstrated in a typical high school physics lab-there is no difference whatsoever between the two explanatory systems. Yet modem physics can explain several critical phenomena that classical physics cannot, phenomena ranging from the microworld of high-energy physics to the macroworld of astrophysics. In a similar fashion, I believe that a Darwinian theory can explain aspects of creative behavior that cannot be handled by traditional theories. For instance, a key component of such a theory is that the creative process is sufficiently blind that ideas ef- fectively emerge in a quasi-random fashion across and within careers. This assumption enables the construc- tion of stochastic models that comprehensively explain and precisely predict several highly distinctive features of creative behavior. Besides those already mentioned in the previous paragraph, these include the specific structure of multiple discoveries (as discussed in the target article) and the explosive growth of scientific knowledge overtime (see Fowler, 1987). It seems most implausible that these inherently stochastic models can ever be accommodated by any theory that does not in-

Actually, although there is no doubt that human beings (creative or not) have the experience of volition, I am not sure whether that experience has a causal role rather than being a mere epiphenomenon of the brain when it enters certain goal states. If one adopts the Cartesian solution to the mind-body problem, then the volitional nature of human creativity has genuine meaning. But if one believes that con- sciousness is a by-product of specific kinds of neurological activity, then there is no profound difference between the creative mind, Skinnerian operant conditioning, and organic evolution.

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clude a quasi-random process at its very core (see also Huber, 1998a, 1998b).

Stemnberg and I do agree on one thing: Darwinian models can be overextended. For example, I share his view that Skinner's Darwinian theory of operant conditioning was extended to phenomena outside its proper explanatory province. Indeed, in my book I indicate several other potential misapplications, especially in the domains of sociobiology and evolutionary psychology. Nonetheless, from my standpoint these unsuccessful explanations frequently represent the application of the wrong Darwinian processes. Skinner's behavioral system fails when the organism has sufficient cognitive complexity to engage in a covert Darwinian process where variations are generated and tested against inter- nal representations of the external world (Campbell, 1960; Dennett, 1995). Likewise, evolutionary psychology often tends to ascribe certain human behaviors to organic evolution when those behaviors might be best credited to cultural evolution, which itself largely oper- ates according to Darwinian principles (Boyd & Rich- ardson, 1985). In short, human beings are the product of several Darwinian processes interacting in extremely complex ways. Darwinian theories fail when one process is granted an explanatory monopoly.

Evolution

Both Feist and Montell discuss the question of the evolutionary origins ofhuman creativity. This issue fas- cinates me as well. A considerable portion of my book is devoted to the evaluation of various proposed explanations and the offering of new accounts. In particular, I treat the relative contributions of both organic and cultural evolution, eventually suggesting that the human creative capacity emerged from the new selection pres- sures on organic evolution that were imposed by the advent of human culture, social learning, intergroup com- petition, and population growth. Rather than repeat these speculations here, I would like to close with an observation about the evolution of evolution.

In my view, one of the most remarkable features about life on this planet is the very creativity of the Dar- winian process in generating higher order Darwinian processes that accelerate the pace ofcreative adaptation. When life began, the only source of variations was er- rors in replicating DNA strands, but soon this process was speeded up by the introduction ofthe sexual recom- bination of genetic material. These two basic processes of primary Darwinism focused on variation-selection at the genotypic level, the changes taking place over con- secutive generations in the history of a species. But eventually these primary processes supported the emergence of secondary Darwinian mechanisms operating at the phenotypic level, the adaptations occurring within

the developmental history of a single organism. These new secondary mechanisms included (a) an immuno- logical system forming new antibodies at a rate that could keep pace with the more rapid evolutionary trans- formation of microorganisms, (b) an environmentally shaped epigenetic system for neurological growth that provided for maximum plasticity in the central nervous system, and (c) a behavioral system for the acquisition of new adaptations through operant conditioning (Cziko, 1995; Dennett, 1995).

Yet these secondary processes were completely outclassed by the emergence of the creative mind. This Darwinian system surpasses all others in its capacity for generating new ideas, including new ways to com- bat disease, to augment neurological functioning, and to expand behavioral expertise. Indeed, judging from the accumulated human cultural heritage, creativity has generated more distinct adaptive forms than any other Darwinian process, primary or secondary (Burge, 1984; Simonton, 1999). Among these new cre- ations, appropriately enough, is Darwinism itself-un- doubtedly one of the most successful of all scientific ideas. And if Darwinism does indeed provide an effective description of the creative process, including that found in Charles Darwin and James Watson, it thereby becomes capable of explaining its own origin and elab- oration in the history of ideas.

Nor has the evolution of evolution ceased with these triumphs. With the advent of genetic algorithms and genetic programming, there now exist computers that solve genuine problems according to explicit Darwinian principles (Holland, 1992; Koza, 1992, 1994). Even more as- tonishingly, these Darwinian computational strategies have recently assumed a guise both radically new and profoundly old. Rather than perform the blind-variation and selective-retention process on strands ofbinary code, the same generic process is implemented on actual strands ofDNA, using the latest techniques of genetic en- gineering (Adleman, 1994). This method of biochemical rather than electronic Darwinism can quickly provide solutions to otherwise computationally intractable puzzles, such as the classic Traveling Salesman problem. Darwin- ian processes have thus evolved from the simplest primary mechanisms to the most complex secondary mechanisms, only to return to its DNA origins, the secondary co-opting the primary process. That complete circle may not mark the end of history or the end of science, but one thing is certain: If Darwinism is truly a religion, then this evolutionary homecoming must count among its greatest miracles.

Note

Dean Keith Simonton, Department of Psychology, University of California, 1 Shields Avenue, Davis, CA 95616-8686. E-mail: [email protected]

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The Continued Evolution of Creative Darwinism