Evolution and Contingency
September 18, 2013 | Posted by Webmaster under Volume 14, Number 2, January 2004 |
|
Arkady Plotnitsky
Theory and Cultural Studies Program
Purdue University
aplotnit@sla.purdue.edu
Review of: Gould, Stephen J. The Structure of Evolutionary Theory.Cambridge, MA: Harvard UP, 2002.
We often complain about long books, and, at nearly 1500 pages, Stephen Jay Gould’s magnum opus is about as long as one could find in the sciences. But then, the actual genre of the book, which is a mixture of science, history of science, and biography, sets it apart from most science books as well, although the approach has its companions and precursors from Galileo’s dialogues (which add literature to the mix) on. We do not, however, always do long books justice either; and I’d urge the readers of this review to give Gould the benefit of the doubt and read the whole book, which, it may be added, is not forbidding in its technical aspects. One could of course benefit considerably even from readings parts of it. Gould must have known that some would, and he offers a summary of the chapters’ content at the outset, which can be used to plot various itineraries through the book. Chapter 1, “Defining and Revising the Structure of Evolutionary Theory,” is almost a book in itself, especially by current publishing standards (The Structure of Evolutionary Theory [hereafter SET] 1-89). Chapter 2, “The Essence of Darwinism and the Basis of Modern Orthodoxy,” offers an introduction to Darwin in general and in a twentieth-century context, and is reasonably self-contained, as well. Gould, however, pleads with his readers to “read the book,” the whole book (SET 89). No doubt the book could be trimmed, but, in this reader’s assessment, not by much (maybe by 150 pages or so), and, in some respects, it may not be long enough. But then perhaps no book, no matter how long, could be in a case like this.
The Tolstoyan, War-and-Peace scale and ambition of the project are not out of place. The book may even be seen as the “War and Peace” of evolution itself (the relative “peace” or more gradual processes of adaptational natural selection punctuated by war-like catastrophes wiping out entire species) and of the history of evolutionary theory, or even of Gould’s own life as a scientist. Evolutionary peace is of course relative at best, a fact reflected in Darwin’s extraordinary (full) title, On the Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life. But then so is Tolstoy’s peace, as familial and societal “wars” are waged in the continuous struggle for social survival and success. Possibly influenced by Darwin’s work, Tolstoy’s concept of history in War and Peace (which contains, as one its two epilogues, a philosophical essay on the nature of history) is itself relevant to Gould’s argument and is invoked by him (SET 1340).
Gould, rightly, sees Darwin’s historicizing of evolution and his conception of history as among his most important contributions, perhaps, combined, the most important one. He also, again, rightly, sees Darwin as a philosophical (rather than only scientific) revolutionary, an aspect of Darwin’s work he addresses at some length (99-103, 117-63). (That Gould himself shares this ambition is evident in the book as well.) That history and, hence, at least some philosophy of history are significant is inevitable, given evolution as the subject of their scientific pursuits, inevitable, that is, once Darwin gives life evolution and thus history. In this case, however, at stake is also the introduction of a new philosophical concept of history, as part of a scientific theory, which is not inevitable, since one can also borrow such a concept from elsewhere. Revolutionary as Darwin is, along with so many others, on this score, he is not without his debts. In particular, Darwin’s concepts of history may be seen as extending Hegel’s. Hegel is, to be sure, only one among Darwin’s precursors, but a more significant one than we might surmise from Gould’s discussion of Darwin’s historical thinking, where Hegel is strangely absent. (Gould does invoke Hegel’s notion of dialectical synthesis [591].) Nietzsche, in singling out Hegel’s unique contribution as a philosopher of history, made the point in strong terms by stating that “without Hegel there could have been no Darwin” (Gay Science 305). This may or may not be true, but, to use Nietzsche’s term, the “genealogy” itself is hardly in question. The general appeal to history is more natural (in either sense) in evolutionary theory than in philosophy. As, however, a structural element of theorizing a given phenomenon (which is also how history works in Darwin, and in Gould), it was largely introduced by Hegel and is arguably his greatest philosophical discovery. It is also worth noting the equally crucial influence of Adam Smith on both Hegel and (in part via Thomas Malthus and against William Paley) Darwin, which Gould stresses in Darwin’s case (59-60, 121-125, 231-32). Both Hegel’s philosophy and Darwin’s theory are, conceptually, forms of economics, theories of gains and losses in the struggle of concepts or living beings for life.
Gould’s own concept of history also follows that of Nietzsche (52, 1214-18). As Gould notes:
Although I am chagrined that I discovered Nietzsche's account [in On the Genealogy of Morals] of the distinction between current utility and historical origin so late in my work, I know no better introduction--from one of history's greatest philosophers to boot, and in his analysis of morality, not of any scientific subject--to the theoretical importance of spandrels and exaptation in the rebalancing of constraint and adaptation within evolutionary theory (Chapter 11, pp. 1214-1218). (52)1
Gould also stresses that Darwin’s theory, especially his nearly unconditional insistence on the organismal character of selection, was deeply indebted to the analogy with theories of morality, specifically, again, Adam Smith’s work (127-36; 596-97). On the other hand, Darwinism is one of Nietzsche’s points of departure for his analysis in On the Genealogy of Morals, a point missed or not addressed by Gould (21). Gould does note similarities with Darwin in Nietzsche’s argument, which he sees as “almost eerie,” but which are, I would argue, inevitable (1217). It would be surprising otherwise, even though Nietzsche famously preferred Lamarck to Darwin, or a certain “Lamarck” to a certain “Darwin.” Gould’s Darwin would be much closer to Nietzsche, and Gould, it is worth noting, gives a well-deserved credit to Lamarck as well (170-92). Had Gould dug into Nietzsche a bit deeper, he could have discovered the conceptual problematic of evolutionary theory there. In any event, Nietzsche takes our understanding of the history of morality in radically new directions, including those that Gould found converging on his concept of evolutionary history.
This concept also serves Gould’s critique of Darwin’s grounding of evolution in organismal selection, a critique in part extracted from Darwin’s argument against its grain, from Darwin’s “battle with himself,” or, one might say, by means of a deconstruction from within Darwin’s argument (135-36, 596-97). A central part of Gould’s program is “the expansion of Darwin’s reliance upon organismal selection into a hierarchical model of simultaneous selection at several levels of Darwinian individuality (gene, cell lineage, organism, deme, species and clade)” (1340). Darwin’s version of Nietzsche’s principle of the distinction between current utility and historical origin is “overly restrictive” and “remains fully adaptational,” as against Gould’s, which extends this principle to the role of different structural elements, such as spandrel and exaptation, in shaping evolution (1229). Applications and implications of this principle extend far beyond this particular case, however, and lead to a radical view of evolution–one of the book’s most important philosophical, as well as scientific, contributions.
There are many other contributions, some equally important, and reflecting equally radical and controversial views. The book is a scientific, philosophical, and cultural document of major significance; the parallels with Galileo, Tolstoy, and Hegel are not fortuitous, and the one with Darwin is unavoidable, given that Gould clearly aims at Darwin’s reach and scale. It is not accidental, either, that one can invoke scientific, philosophical, and literary works here, even apart from the role literature and art play in Gould’s argument and exposition. At the same time, the links to the ideas of such authors as Nietzsche, whom Gould, again, follows expressly, or (Gould might have been surprised to hear this) Derrida and Deleuze, and Gould’s inescapable presence in the current cultural debates also make the book a significant document of postmodern thought and culture. This significance is further amplified by the shift from physics to life sciences and information sciences, and their relationships (for example, in the genome project) as primarily defining the relationships between science and culture during the same postmodernist period. Physics retains its scientific and cultural role, in part in conjunction with information sciences, as in quantum information theory, and new biology, specifically via chaos and complexity theory (an icon, sometimes abused, of many recent discussions in the humanities as well). Even though not given a major treatment, complexity theory and its application in evolutionary theory, especially in Stuart Kauffman’s work, play an important role in Gould’s argument for extending and radicalizing Darwin (SET 1208-14).
This argument is for the extension of evolutionary theory beyond what Gould calls the modern synthesis of (the more traditional) Darwinism, presented in Part I, “The History of Darwinian Logic Debate,” toward a different type of evolutionary theory presented in Gould’s argument in Part II, “Toward a Revised and Expanded Evolutionary Theory.” The key aspects of both logics are explained from the outset, where Gould uses the memorable image of Agostino Scilla’s corals as a symbol of Darwin’s theory, to be reshaped by Gould’s revisions, even against Darwin’s favorite “tree of life,” although, as will be seen, both share their essential tree-like structure (16-19, 97). Darwin’s first book was on corals, and it is honored by Gould with “the coral reef principle” of sequencing of Darwin’s historical way of thinking (103-4). This joint structure–of Darwin’s theory and Gould’s revision–is reiterated throughout the book. It is even restated, with a considerable mastery of composition, in the final and the longest footnote in the book on page 1313 and then yet again in (almost) closing the book. To cite this final summary:
In most general terms, and in order to form a more perfect union among evolution's hierarchy of structural levels and tiers of time, this revised theory rests upon an expansion and substantial reformation of all three central principles that build the tripod of support for Darwinian logic: (1) the expansion of Darwin's reliance upon organismal selection into a hierarchical model of simultaneous selection at several levels of Darwinian individuality (gene, cell lineage, organism, deme, species and clade); (2) the construction of an interactive model to explain the sources of creative evolutionary change by fusing the positive constraints of structural and historical pathways internal to the anatomy and development of organisms (the functionalist approach); and (3) the generation of theories appropriate to the characteristic rates and modalities of time's higher tiers to explain the extensive range of macroevolutionary phenomena (particularly the restructuring of global biotas in episodes of mass extinction) that cannot be rendered as simple extrapolated consequences of microevolutionary principles. (1340)
This is an immense program, and one can, obviously, offer no more than a sketch of some among its lineaments here. I shall assess Gould’s argument from a particular angle, indicated by my title, “evolution and contingency,” which will, however, allow me to address some among the most fundamental aspects of the argument. Many other aspects of it, some of them important, will have to be sacrificed. Most of these, however, are among the better known and the more extensively commented-upon aspects of Darwin’s work or post-Darwinian evolutionary theory and of Gould’s work. Given this history, Gould’s theoretical and historical arguments in the book are bound to be challenged by evolutionary theorists and historians of science. Here, however, in a more “positive spirit,” such as Nietzsche invokes in On the Genealogy of Morals, I will look beyond these specific points of agreement or disagreement to consider some of the more radical questions and challenges posed by the book itself (18).
My angle is defined by the joint role of chance and discontinuity (as in Gould’s “punctuation”) in evolution and in the structure (or history) of evolutionary theory and, indeed inevitably, beyond them. The scientific and epistemological significance of this problematic in evolutionary theory and elsewhere in modern science is unquestionable.2 It is, I would argue, culturally significant as well. At least from the mid-nineteenth century on, our culture may be seen as the culture of chance, or of the confrontation with chance, a confrontation which, in the absence of any counterbalancing causality, it may not yet be ready to accept (SET 1332-33). I speak of the role of chance (rather than simply chance), since the argument of the book is not primarily about chance but is (more) about causality and organization (46-47, 1339). And yet, from Darwin on, chance is seen as an essential force in evolution, which gives the concept of chance a central role in the structure of evolutionary theory, especially as it is developed in Gould’s work, including in this book. I shall link causality and chance in the concept of contingency (which is also Gould’s preferred concept) as the (inter)play of both. The idea originates with Democritus and extends through a long chain of thinkers to Derrida in particular, and is here invoked by Gould via the complexity theorists Jacques Monod and Stuart Kauffman (144, 1336).3 My appeal to contingency stresses the significance of theorizing chance in evolution, as opposed to causal explanation, while keeping the latter as part of the overall theory. This emphasis is consistent with both Darwin’s and Gould’s views, different as these are in their overall theoretical structure. Gould’s own use of contingency is defined at the outset, in his biographical “Apologia Pro Vita Sua,” complementing his historicist philosophy and attitude, his “love of history in the broadest sense.” He writes:
Finally, my general love of history in the broadest sense spilled over into my empirical work as I began to explore the role of history's great theoretical theme in my empirical work as well--contingency, or the tendency of complex systems with substantial stochastic components, and intricate nonlinear interactions among components, to be unpredictable in principle from full knowledge of antecedent conditions, but fully explainable after time's actual unfoldings. (46; emphasis added)
This concept of contingency is close, but not identical, to that of chaos and complexity theories (specifically as developed in Kauffman’s work), as the invocation of the terms “complex systems” and “nonlinearity” suggests. While granting the significance of the Gouldian dynamics of contingency in evolution, I shall introduce a broader and in some respects more radical view of chance (conceived in part on the model of quantum theory) and, hence, of contingency, and suggest that this type of chance plays a role in evolutionary theory. Overall, I shall argue that it is the structure of evolutionary contingency–of what types of chance, of causality, and of the relationships between them–that is, ultimately, at stake in Gould’s argument. Gould’s book directs us toward a different, higher-level, synthesis between the modern (Darwinist) synthesis presented in Part I and Gould’s argument presented in Part II, “Toward a Revised and Expanded Evolutionary Theory.” This new synthesis, for which, as Gould says, the Hegelian triad of thesis-antithesis-synthesis may be inadequate, is not offered in the book, which only directs us “toward” it (591). The book does not have and did not aim to have a Part III, but it did aim to argue for such a new synthesis and to prepare for it–a Herculean labor and an immense achievement already (SET 591-92; also pp. 46-47, 1332-43). It is clear, however, that, as announced by Gould at the outset, following his definition of contingency, and as sketched in the epilogue, that new synthesis is fundamentally defined by the role of contingency in the structure of evolutionary theory. As Gould writes:
This work [his previous work on contingency] led to two books on the pageant of life's history [Wonderful Life: The Burgess Shale and the Nature of History [1989] and Full House: The Spread of Excellence from Plato to Darwin [1996]). Although this book, by contrast, treats general theory and its broad results (patterns vs. pageant in terms of this text), rather than contingency and the explanation of life's particulars, the science of contingency must ultimately be integrated with the more conventional science of general theory as explored in this book--for we shall thus attain our best possible understanding of both pattern and pageant, and their different attributes and predictabilities. The closing sections of the book (pp. 1332-1343 of Chapter 12) offer some suggestions for these future efforts. (46-47)
I shall have a chance to return to the image of pageant, a special favorite with Gould, used three times here. The problematic itself developed in these closing sections may, as I said, take us toward notions of chance and contingency more radical than Gould’s, but not more than what may be demanded from our theories by evolution–or by life, to which both Darwin and Gould appeal at crucial junctures. The concept of evolution may be insufficient in turn, even as it emerges in all its architectural complexity in Darwin’s or Gould’s cathedral, a persistent image in the book, almost closing it as well–almost: ultimately Darwin’s “the tree of life” does. Gould’s argument is, however, framed by Milan’s Duomo and San Marco in Venice, with the architecture of New York taking over in the Epilog (SET 1-6, 1249-55, 1339). Would life, however we image it, be sufficient? Do we, in truth, have such a concept qua concept, life, which doubt compelled Shelley to ask in his great unfinished poem The Triumph of Life, the poem that his death interrupted, punctuated, on this very question: “What is Life?”? Would even a double question mark be enough?
Gould’s book was published posthumously in 2002 (Gould died earlier the same year). Forty years earlier, in closing his The Structure of Scientific Revolutions, Thomas Kuhn addressed Darwin’s evolutionary theory, a primary inspiration for Kuhn’s own work. Kuhn noted that Darwin’s most innovative and radical idea, which “bothered many professionals most was neither the notion of species change nor the possible descent of man from apes,” but instead that of the abolition of evolutionary teleology (171-72). These, especially, as Gould stresses, the first one, remain important conceptually, historically, and culturally (SET 99-103). Nevertheless, Kuhn is right. As he elaborates:
The evidence pointing to evolution, including the evolution of man, had been accumulating for decades, and the idea of evolution had been suggested and widely disseminated before. Though evolution, as such, did encounter resistance, particularly from some religious groups, it was by no means the greatest of the difficulties the Darwinians faced. That difficulty stemmed from the idea [of non-teleological, undirected evolution] that was more nearly Darwin's own. All the well-known pre-Darwinian evolutionary theories--those of Lamarck, Chambers, Spencer, and the German Naturephilosophen--had taken evolution to be a goal-directed process. The "idea" of man and of the contemporary flora and fauna was thought to have been present from the first creation of life, perhaps in the mind of God. That idea or plan had provided the direction and the guiding force to the entire evolutionary process. Each new stage of evolutionary development was a more perfect realization of a plan that has been present from the start. (171-72)
Gould’s book shows the enormous richness and complexity of this history and its transition to Darwinism, well beyond what Kuhn could convey here and, he argues, beyond what Kuhn’s conception of history of science could offer (SET 967-70). Darwin enters the stage set by this history with “his most significant and least palatable suggestion”:
For many men the abolition of that teleological kind of evolution was the most significant and least palatable of Darwin's suggestions. The Origin of Species recognized no goal set either by God or nature. Instead, natural selection, operating in the given environment and with the actual organisms presently at hand, was responsible for the gradual but steady emergence of more elaborate, further articulated, and vastly more specialized organisms. Even such marvelously adapted organs as the eye and hand of man--organs whose design had previously provided powerful arguments for the existence of a supreme artificer and an advance plan--were products of a process that moved steadily from primitive beginnings but towards no goal. The belief that natural selection, resulting from mere competition between organisms for survival, could have produced man together with the higher animals and plants was the most difficult and disturbing aspect of Darwin's theory. What could "evolution," "development," and "progress" mean in the absence of specified goal? To many people, such terms suddenly seemed self-contradictory. (Kuhn 172)
Several key Darwinian concepts are indicated here, even beyond the abolition of evolutionary teleology, most especially “gradualism” or a more general principle of “gaining the knowledge of the world” or natural history from the behavior of its small or even infinitesimal parts or changes and their continuity.4 This principle may be seen as defining the scientific paradigm and paradigm change, established not only by Darwin’s work but by such contemporary theories as James Clerk Maxwell’s field theory of electromagnetism and Bernhard Riemann’s mathematics (or earlier differential calculus, since, like all paradigm changes, this one has a long pre-history as well), and extending to Einstein’s work in relativity. Leibniz, a co-inventor of differential calculus and a major influence on Riemann, was arguably the most significant precursor, as Gould notes, rightly coupling him with Linnaeus–although, as Gould explains, Charles Lyell may be an equally important influence upon Darwin in this respect (150, 149, 479-86). In science, one needed quantum theory to announce a new paradigm, although there are earlier intimations, especially as concerns the idea of chance, as in thermodynamics, and philosophically one can trace this history still earlier. The principle cannot be sustained in Gould’s version of evolutionary theory either, which shift has its history in turn, at least from Georges Cuvier on (484-92).
Along with most Darwinian concepts, those just mentioned are given a powerful critical treatment by Gould throughout the book, using the term “critical” in Kant’s sense of critique as an exploration of fundamental concepts in a given field and of the conditions for their effective deployment there. Decisive to this critique are the questions of chance and discontinuity, and the relationships between them, in evolution and specifically in the non-teleological view of evolution advanced by Darwin. Both Kuhn and Gould fundamentally link the structures of biological and scientific evolutions, or revolutions, to chance and discontinuity (“revolution” in Kuhn and “punctuation” in Gould), in Kuhn’s case under the impact of quantum theory. Gould could hardly have been unaware of the parallel between Kuhn’s and his own title, even if he did not intend a direct allusion. Nor could he have been unaware of Kuhn’s elaborations just cited, and it is of some interest that he does not comment on them or Darwin’s influence on Kuhn’s work. Gould does discuss Kuhn’s ideas concerning scientific revolution and acknowledges Kuhn’s significance and influence in this respect, as well as noting certain Darwinian elements in Kuhn’s later (1969) “Postscript” to his book in the context of the concept and the very term “punctuation” (SET 967-70).
Now, all teleology is, by definition, causal, even if, as I shall explain, this causality is hidden behind (the appearance of) chance, and, by virtue of its causal nature, essentially continuous. Accordingly, the questions of chance and discontinuity, or of the relationships between causality and chance and continuity and discontinuity (or among all of these), may be seen as less interesting in this case. On the other hand, the role of chance and discontinuity in non-teleological views of evolution is a subtle issue, which caused a complex and sometimes ambivalent attitude on the part of Darwin himself, specifically in the relations between more local (such as adaptation) and more global evolutionary dynamics (SET 1333-36). Can we dispense with chance and discontinuity, given the abolition of teleology? What are the dynamics of chance or discontinuity? How are the latter linked to causalities and continuities? What are the relationships between chance and discontinuity, or causality and continuity? These are decisive questions. For, at least in evolution, chance without causality, or discontinuity without continuity, would be almost as problematic and scientifically uninteresting as causality, natural or divine, absolutely without chance (100-2). In question is an interplay of chance and causality or necessity, of which Democritus was perhaps first to speak, coupled, if one wants to trace it to the pre-Socratics, to the Heraclitean becoming, the never-the-same flow of evolution, but, on this view, the flow interrupted and reshaped by discontinuity. With Darwin and, then, with Nietzsche, this double interplay acquires an extraordinary and ultimately irreducible complexity and, as Derrida argues, becomes ultimately incalculable, preventing us from ascertaining whether, at least, some events are products of chance or causal dynamics (7).5
Gould’s own contribution to evolutionary theory belongs primarily to this problematic of causality and chance, within contingency, or (sometimes correlatively) between punctuation and continuity. It is, again, important that all these elements and various relationships between and among them are engaged with by Gould and made parts of the structure of evolutionary theory, as he sees it. Thus, for example, the continuity and persistence of form (morphological continuity) or that of other constraints is just as important as punctuation, as both equally work against orthodox Darwinism. This type of complexity is found, however, throughout Gould’s arguments, for and against Darwin’s theory, and translates into the relationships, conceptual or historical, between various strains of evolutionary theory. Granting this complexity, one might, nevertheless, argue that the most radical implication, if not the idea, of Darwin’s theory is that of the role of chance, also in its discontinuous, interruptive effect, as the primary force of evolutionary change. As Gould says:
If, however, as the central thesis of this book maintains and the [postmodern?] Zeitgeist of our dawning millennium no longer rejects [in contrast to evolutionists and paleontologists of the preceding generations], we cannot validate the actuality of mammalian success by general principles, but only as a happy (albeit entirely sensible) contingency of a historical process with innumerable alternatives that didn't happen to attain expression (despite their equal plausibility before the fact), then we must face the philosophical question of whether we have surrendered too much [of contingency] in developing a more complex and nuanced view of causality in the history of life. (SET 1332; emphasis added)
On this view, the rise of humans, as conscious animals, is, too, a product of contingency, of a series of contingent, if sensible accidents, perhaps glorious, as Gould once called them, but accidents nonetheless. The question becomes what is the particular character of this chance and, hence, of the interplay of chance and causality defining the contingency/ies of evolution. The emphasis on contingency, as the interplay of chance and causality, rather than on chance alone, is crucial, but the character of contingency is defined by the character of chance within it. This is not to say that the nature of causalities and necessities involved in evolution is not important; quite the contrary, and we need as rich and complex conceptions and theories of causal processes as we can develop. The same argument applies to continuity and discontinuity, and the relationships between them, or between them and causality and chance. Gould’s elaboration opening the section “Undirected,” dealing with Darwin’s abolition of teleology, indicates this complexity as well, in part by way of warning (143-46). Gould stresses the contingent and yet also notes the crucial significance of chance in shaping this complexity, including as concerns “the direction of evolutionary change.” He writes:
Textbooks of evolution still often refer to variations as "random." We all recognize this designation as a misnomer, but continue to use the phrase by force of habit. Darwinians have never argued for "random" mutation in the restricted and technical sense of "equally likely in all directions," as in tossing a die. But our sloppy use of "random" [...] does capture, at least in a vernacular sense, the essence of the important claim that we do wish to convey--namely, that variation must be unrelated to the direction of evolutionary change; or, more strongly, that nothing about the process of creating raw material biases the pathway of subsequent change in adaptive directions. This fundamental postulate gives Darwinism its "two step" character, the "chance" and "necessity" of Monod's famous formulation--the separation of a source of raw material (mutation, recombination, etc.) from a force of change (natural selection). (144)
Monod’s formulation captures well the Darwinian contingency, to which Gould adds the chance of punctuation, or, conversely, additional morphological causalities and/as continuities, thus reshaping the overall structure of evolutionary contingency. As will be seen, there may be more of tossing of the dice in mutation. The problem, however, may indeed be that the complexity of the process prevents us from properly assessing how much, if at all, loaded these dice are. In any event, the mutations in question are random enough, at least as “unrelated to the direction of evolutionary change,” as Gould rightly stresses. That is, they are random enough to change our view of evolution. The evolutionary survival of such mutations is of course a still different bet, more Darwinian (gradualist and adaptational) or more Gouldian, which supplements the Darwinian bet with other elements, such as the contingency of punctuation. Even well-adapted species, such as dinosaurs, or potentially well-adaptable species in the proper evolutionary contexts of their emergence and developments, could be “punctuated” out of existence due to external (geological or cosmic events) or other changes in the context.
It is true that, as I have indicated, this particular book is, at least overtly, not about contingency. Gould stresses this point in the Epilog:
But this book--entitled The Structure of Evolutionary Theory--does not address the realm of contingency as a central subject, and fires my very best shot in the service of my lifelong fascination for the fierce beauty and sheer intellectual satisfaction of timeless and general theory. I am a child of the streets of New York; and although I reveled in a million details of molding on the spandrel panels of Manhattan skyscrapers, and while I marveled at the inch of difference between a forgotten foul ball and an immortal home run, I guess I always thrilled more to the power of coordination than to the delight of a strange moment--or I would not have devoted 20 years and the longest project of my life to macroevolutionary theory rather than paleontological pageant. (1339)
And yet, even as the book only looks toward and prepares the ground for the synthesis of the science of general theory and the science of contingency in evolutionary theory, while primarily doing general theory, contingency is everywhere in this book. This is hardly surprising. Indeed, there is a “because” behind my “and yet.” Contingency is irreducibly complicit with the general theory engaged with by the book, or in Darwin’s work and most versions of Darwinism, which, accordingly, defines the character of the future theory that Gould has in mind. To give one example, which is, however, central to Gould’s argument, Nietzsche’s principle, mentioned earlier, of “the distinction between current utility and historical origin” shapes (albeit differently) both Darwin’s and Gould’s arguments. “Nietzsche recognizes (as Darwin did),” that this principle also
establishes grounds for contingency and unpredictability in history--for if any organ [such as the eye or hand], during its history, undergoes a series of quirky shifts in function, then we can neither predict the next use from a current value, nor can we easily work backwards to elucidate the reason behind the origin of the trait. (1217)
Hence, the irreducible role of contingency and indeed chance (“unpredictability”) in the general theory, Darwin’s and even more so Gould’s. There could be no Darwin without contingency anymore than without history, as Darwin’s concept of history is itself crucially shaped by the concept of contingency as the interplay of chance and causality (without ultimate causes) in evolution.
Gould “embraces this apparent paradox with delight”: “I have championed contingency, and will continue to do so, because its large realm and legitimate claims have been so poorly attended by evolutionary scientists who cannot discern the beat of this different drummer while their brains and ears remain tuned to the sounds of general theory” (1339; emphasis added). The paradox itself is of course only apparent, or reveals a more subtle theoretical logic. One might also say that the paradox interrupts and destabilizes the accepted logic of evolutionary theory, and leads to a new logic and, with it, new evolutionary theory, which thus “refute” the paradox, along with (some) of the Darwinisms and even (some) Darwin. As Gould adds, rightly assessing his book (it is difficult to do better): “So yes, guilty as charged, and immensely proud of it! The most adequate one-sentence description of my intent in writing this volume flows best as a refutation to the claim of paradox just above […]” (1339). It is a long sentence, but a good one, both in content and in form, structure, in its continuous flow, which I punctuate a bit here:
This book attempts to expand and alter the premises of Darwinism, in order to build an enlarged and distinctive evolutionary theory that, while remaining within the tradition, and under the logic, of Darwinian argument, can also explain a wide range of macroevolutionary phenomena lying outside the explanatory power of extrapolated modes and mechanisms of microevolution, and that would therefore be assigned to contingent explanation if these microevolutionary principles necessarily build the complete corpus of general theory in principle. To restate just the two most obvious examples of the higher tiers of time exemplified in this chapter: (1) punctuated equilibrium establishes, at the second tier, a general speciational theory of cladal trending, capable of explaining a cardinal macroevolutionary phenomena that has remained stubbornly resistant to conventional resolution in terms of adaptive advantages to organisms, generated by natural selection and extrapolated through geological time; (2) catastrophic mass extinction at the third tier suggests a general theory of faunal coordination far in excess [...] of what Darwinian microevolutionary assumptions about the independent history of lineages under competitive models of natural selection could possibly generate. (1339-1340)
On the other hand, as I have indicated, while contingency and, within contingency, randomness and chance, are fundamental to Gould’s theory of evolution, this theory itself, even when dealing with contingency, is, as is Darwin’s, ultimately more interested in causality, without the ultimate cause, than in chance as such. The qualification is, again, crucial, for “following Hutton, Lyell, and many other great thinkers,” Darwin “foreswore (as beyond the realm of science) all inquiry into the ultimate origins of things” (SET 101). In particular and most significantly, this attitude is correlative to the view that the key causalities, either more Darwinian or more Gouldian, in question in the theory are initiated by random events. These events must thus also be treated structurally as discontinuous in relation to these new causal chains as in relation to previous causal chains. In other words, the dynamics of these chains is initiated by but does not depend on and is dissociated from what triggers them. The absence of the single overall teleology, or a single overall archeology (the ultimate origin), of evolution follows automatically. While incorporating Darwinian mutations (as of secondary significance, without the ultimate creative evolutionary force), Gould’s theory also deals with causal sequences resulting from or shaped by random events, such as punctuations, and in itself qua theory concerns only these causal sequences, and not random events initiating or affecting them. As in Darwin’s case, the specific character of the causalities in question, however, gives this theory its explanatory and descriptive power, and Gould’s book offers ample evidence of this power along both lines, Darwinian and Gouldian, or in joining them.
Gould’s concept of contingency is subordinated and indeed defined by the agenda just explained. To restate his definition, contingency is “the tendency of complex systems with substantial stochastic components, and intricate nonlinear interactions among components, to be unpredictable in principle from full knowledge of antecedent conditions, but fully explainable after time’s actual unfoldings” (46; emphasis added). Analogously (although not identically) to chaos or complexity theory, the dynamics in question are highly nonlinear but ultimately causal, although, in contrast to most situations considered by chaos or complexity theory, these dynamics are, again, initiated by random events. More accurately, these events are seen as random in the context of evolution and may be causal in other contexts, geological, cosmic, or others, but, if they are causal in these latter contexts, these causalities (say, those responsible for the collisions between the Earth and asteroids that destroyed so many well-adapted species) are bracketed. They are not part of the structure of evolutionary theory. Accordingly, Gould’s concept of contingency is well suited to the workings of punctuation or other nonadaptational events and forces at work in evolution that he considers. As will be seen, however, some chance events in evolution, such as, possibly, mutations, may not be bracketed in this way, although they are of course in Darwin’s theory. And yet they may still need to be left to chance, without any hope of theorizing any causality behind them. Would theorizing such events, with or without causality behind them, be part of Gould’s new synthesis, or does he merely mean expanding causal macroevolutionary patterns initiated by random events and their relationships, positive or negative, to microevolutionary dynamics? Could it be, once causality is suspended? Could they be theorized? What would the theory of chance events without causality behind them or of particulars without relations to the whole be, and what kind of explanatory specificity could it offer? I shall return to these questions below. A broader overarching point can be made now, however, to convey one of the most important lessons of this book.
Evolutionary theory may demand from us as complex a combination of chance and causality (or necessity) as we can develop, indeed many a complex combination of both, to a degree of complexity arguably unique in the natural sciences. It is true that, if we consider physics as a conglomerate of its various theories, one can make a similar case there as well. Indeed, as will be seen, one of the key questions here is what a general or unified theory joining such theories, say, as branches of a single tree, would be, if it were possible. For the moment, Gould’s argument is that, along with the Darwinian contingency (as part of a more gradual dynamics of evolutionary change), random discontinuous punctuation is an equally and even more significant force of change, thus leading him to a more radical and more complex concept of evolutionary contingency. The contingency part of this argument (whereby causal chains are initiated or reshaped by chance events that themselves are not included in these chains and are, thus, also discontinuous from them) is, again, decisive. We may need still more complex structure(s) of contingency, however, extending the spectrum of contingency, and thus of both chance and causality, even further. In the case of the history of life, of its, to cite, with Gould, Shakespeare’s most famous lines from The Tempest, continuous, incessant “sea change into something rich and strange,” we might need to do so as much as we possibly can (The Tempest I, ii, 403; SET 24).
With this argument for a necessarily broad spectrum of causality, chance, and contingency in mind, the question becomes that of the character of chance as such. In particular, the question is whether chance is a manifestation of causality or necessity, however hidden or remote, or not. These two alternatives define the two concepts of chance that I shall discuss–classical, which entails a hidden causality or necessity behind chance, and nonclassical, in which case we do not or even cannot assume any causality behind it. Nonclassical contingency is defined, accordingly, as contingency involving nonclassical chance in one way or another, which is the case in Darwin’s or Gould’s view of evolutionary contingency. It is worth qualifying that for the moment I am concerned with what is responsible for chance, with the effects of chance, with random effects, as opposed to the effects of chance events upon a given causal dynamics or engendering new causalities, the main concern of Darwin and Gould. Their argument for giving chance a shaping role in evolution, however, remains important in this context as well. For, as explained above, in relation to the dynamics these interruptive events (such as mutational variations or exterior punctuations) trigger or enter, they are nonclassical, even if the dynamics responsible for the emergence of such events is classical (causal), since this dynamics itself is not included in evolutionary theory. The unpunctuated evolutionary dynamics occurring between such events is considered by the theory as causal or classical, which may not be the case elsewhere, for example, in quantum theory, and, as I indicated above, mutations may need to be considered in a more radically nonclassical way.
By “chance” itself, it is worth reiterating, I mean a manifestation of the unpredictable (possibly within some dynamics of contingency, as the interplay of causality and chance). A chance event is an unpredictable, random event, whether it ultimately hides some underlying causal dynamics, as in the case of classical chance, or not, as in the case in nonclassical chance. For example, when they occur in classical physics, randomness and probability result from insufficient information concerning systems that are at bottom causal. It is their complexity (due, say, to the large numbers of their individual constituents, as in the kinetic theory of gases) that prevents us from accessing their causal behavior and making deterministic predictions concerning this behavior. I here distinguish causality and determinism. I use “causality” as an ontological category relating to the behavior of the systems whose evolution is defined by the fact that the state of a given system is determined at all points in time by its state at a given point. (In the present context, causal and classical are the same.) I use “determinism” as an epistemological category having to do with our ability to predict exactly the state of a system at any and all points once we know its state at a given point.
In physics, classical mechanics deals deterministically with causal systems; classical statistical physics deals with causal systems, but only statistically, rather than deterministically; and chaos theory or complexity theory deals with systems that are, in principle, causal, but whose behavior cannot be predicted even in statistical terms in view of the highly nonlinear character of this behavior. Gould’s evolutionary contingency involves an analogous causal stratum, although the specific dynamics operative there differs from that of complexity theory, for example, as developed in the evolutionary context in Kauffman’s work. All these theories are causal and hence classical insofar as they deal, deterministically or not, with systems that are assumed to behave causally, in contrast to quantum theory and possibly evolutionary theory. Quantum theory offers predictions, of a statistical nature, concerning the systems that may not be and, in most versions of the theory, indeed cannot be considered as causal or, more generally, subject to any realist description, and thus the events such systems trigger cannot be “fully [or even partially] explainable after time’s actual unfoldings,” along the lines of Gould’s contingency. Quantum theory only predicts, statistically, certain events (in the manner of outcomes of tossing dice) but does not explain the physical processes through which these events come about. Even though the probabilistic predictions of quantum mechanics are subject to rigorous mathematical laws, in this case, in contrast to that of classical statistical physics, randomness and probability do not arise in view of our inability to access the underlying causal dynamics determining the behavior of quantum systems.6 It does not appear possible to assume such a behavior to be causal. Accordingly, in quantum mechanics we confront nonclassical chance in the case of all events considered by the theory, without assigning or assuming any causality between these events, rather than only in the case of certain events punctuating causal chains, as in the case of evolutionary theory and its dynamics of contingency. Although not without parallels or predecessors elsewhere, the physical theories just described are our primary scientific and mathematical-scientific models of chance, including in biology and evolutionary theory, which cannot as yet escape “physics envy,” even when they exercise proper ambivalence in this attitude (SET 1209).
Classically, then, chance or, it follows, the appearance of chance is seen as arising from our insufficient (and perhaps, in practice, unavailable) knowledge of a total configuration of the forces involved and, hence, of a lawful causality that is always postulated behind an apparently lawless chance event. If this configuration becomes available, or if it could be made available in principle, the chance character of the event would disappear. Chance would reveal itself to be a product of the play of forces that, however complex, is, at least in principle if not in practice, calculable by man, or at least by God, who, in this view, indeed does not play dice, as Einstein famously said, or at least always knows how they will fall. In other words, in practice, we only have partially available, incomplete information about chance events, which are, nonetheless, determined by, in principle, a complete architecture of causality or necessity behind them. This architecture itself may or may not be accessible in full or even partial measure. The presupposition of its existence is, however, essential for and defines the classical view as causal and, correlatively, realist. Subtle and complex as they may be, all scientific theories of chance and probability prior to Darwin’s evolutionary theory (and then, still more radically, quantum theory), and many beyond them, as well as most philosophical theories of chance, are of the type just described. They are classical. Combined, two of Alexander Pope’s famous utterances, the closing of Epistle 1 of An Essay on Man and his “Proposed Epitaph for Isaac Newton,” encapsulate the classical view of chance or, conversely, causality and law:
All Nature is but art, unknown to thee;
All chance, direction, which thou canst not see;
All discord, harmony not understood;
All partial evil, universal good:
And, spite of pride, in erring reason's spite,
One truth is clear: Whatever IS, is RIGHT.
(An Essay on Man, Epistle 1, 289-94)
Nature and Nature's laws lay hid in night;
God said, let Newton be! and all was light.
(“Proposed Epitaph for Isaac Newton, who died in 1727”)
Gould cites the immediately following passage from An Essay of Man, opening Epistle 2, which considers the nature of man, while Epistle 1 considers the nature of nature itself, as best seen by man, or by best men. Women are yet another subject in Pope. On the other hand, some women writers, such as Emily Brontë, invoked by Gould alongside Tolstoy, give us a more subtle perspective on the world, as defined by chance and contingency (SET 1340). In the passage cited by Gould, Pope writes:
Know then thyself, presume not God to scan;
The proper study of Mankind is Man.
Placed on this isthmus of a middle state,
A being darkly wise, and rudely great [...]
He hangs between; in doubt to act, or rest;
In doubt to deem himself a God, or Beast;
In doubt his Mind or Body to prefer.
Born but to die, and reas'ning but err;
Alike in ignorance, his reason such,
Whether he thinks too little, or too much:
Chaos of Thought and Passion, all confus'd;
Still by himself abus'd, or disabus'd;
Created half to rise, and half to fall;
Great lord of all things, yet a prey to all;
Sole judge of Truth, in endless Error hurl'd:
The glory, jest, and riddle of the world!
(An Essay on Man, Epistle 2, 1-18)
I give a slightly fuller quotation, including the first two lines, which tell us that, as far as science is concerned, we no longer need to appeal to any theological considerations, as (the genius of) Newton is sufficient, but also necessary–a necessary and sufficient condition, as mathematicians say. This passage appears at an important juncture of Gould’s book, in the opening chapter of Part II, “Toward a Revised and Expanded Evolutionary Theory,” as he begins his build-up of his revisionist theory, from the argument concerning, to cite the title of the chapter, “Species as Individuals in the Hierarchical Theory of Selection” (SET 680). It is hardly surprising that Gould sees Pope’s passage “as composed for a quite different, but interestingly related purpose” (680; emphasis added). Pope’s biological, geological, and cosmological examples and hierarchies are of much interest here. To be sure, Pope’s pre-Darwinian and even pre-Linnaen “chain of beings” is well short of evolution. It can, however, be given a teleological, directed historical and thus evolutionary dynamics. Undirected and contingent history is a far more radical and difficult move, which requires the genius of Darwin. With Darwin and then with new non-Newtonian physics, at God’s command or not, a different light appears and different night must be assumed. Man’s view, even at its best, may be even more “parochial” (Gould’s word) than Pope thought, its parochialism lying, ironically, in the assumption of a plan in this maze of Nature–“a mighty maze! but not without a plan” (Epistle 1, 6)–or of “God-does-not-play-dice” necessity and order in this “one stupendous whole” (Epistle 1, 267), or, for that matter, in an assumption of wholeness or oneness, even while renouncing any possible understanding of this plan in its working specificity. Einstein would not be quite so modest and would aim to know how it all works. Bohr, in response, argued that, in order to do quantum theory, we might have to be even more modest than Pope urges us to be. As Gould says:
The problem can be summarized with another, much older, classical quotation. "Man is," as Protagoras wrote in his wonderfully ambiguous epigram, "the measure of all things"--ambiguous, that is, in embodying both positive and negative meanings: positive for humanistic reasons of ubiquitous self-valuing that might lead to some form of universal brotherhood and compassion; but negative because our own "measure" can be so parochially limiting, and therefore so conducive to misunderstanding other scales if we must assess these various domains by the allometric properties of our limited estate. (680-81)
Ultimately, this parochialism may be irreducible. Gould, in the epilogue, offers a powerful critique of the classical view in science. Thus, he says:
I confess that, after 30 years of teaching at a major university, I remain surprised by the unquestioned acceptance of this view of science--which, by the way, I strongly reject for the reasons exemplified just below--both among students headed for a life in this profession, and among intellectually inclined people in general. If, as a teacher, I suggest to students that they might wish to construe probability and contingency as ontological properties of nature, they often become confused, and even angry, and almost invariably respond with some version of the old Laplacean claim [of the underlying ultimate causality of nature]. In the short, they insist that our use of probabilistic inference can only, and in principle, be an epistemological consequence of our mental limitations, and simply cannot represent an irreducible property of nature, which must, if science works at all, be truly deterministic. (1333)
At least it must be truly causal, on the present definition. On the other hand, one should not perhaps be surprised, given that the classical view has the backing of a great many major figures in modern science and beyond it, beginning with Einstein, for whom quantum mechanics was almost not science on these very grounds.
Inspired by, among others, Lucretius (whose well-known passages could also be cited here), Milton’s description of chaos in Paradise Lost gives us a subtler picture of chance:
Before thir [Satan's, Sin's and Death's] eyes in sudden view appear
The secrets of the hoary deep, a dark
Illimitable Ocean without bound,
Without dimension, where lengths, breadth, and highth,
And time and place are lost; where eldest Night
And Chaos, ancestors of Nature, hold
Eternal Anarchy, amidst the noise
Of endless worth, and by confusion stand.
[...] Chaos Umpire sits,
And by decision more imbroils the fray
By which he Reigns: next his high Arbiter
Chance governs all. Into this wild Abyss,
The Womb of Nature, and perhaps her Grave,
Of neither Sea, nor Shore, not Air, nor Fire,
But all of these in thir pregnant causes mixed
Confus'dly, and which this must ever fight,
Unless th's Almighty Maker them ordain
His dark materials to create more Worlds,
(Book II, 890-916)
This extraordinary vision is closer to the nonclassical view of chance, if not quite as radical by giving God at least a chance to govern chance and shape it into order. It should be noted, though, that the view of chaos given here is how Satan and his family entourage see it, and it may be that, as in Pope, in Milton, too, there would be no randomness and chaos at the ultimate level, unavailable to anyone “except to God alone” (Book III, 684).
In any event, to reach the conceptual-epistemological structure of evolutionary theory, as advocated by Gould, one needs to remove God from the structure here proposed, or again, with Darwin, “foresw[ear] (as beyond the realm of science) all inquiry into the ultimate origins of things” (SET 101). From this perspective, evolutionary processes are seen as giving rise to causal sequences and ordered structures without presupposing the overall underlying or primordial causality or order, either exterior or integrated into the evolutionary process. Random impacts upon evolution may, again, come either from within, through mutations or constraints, for example, or from exterior punctuations. In question is, accordingly, first, the interplay of chance and causality (or necessity), and, then, the order (life is a highly ordered phenomenon) emerging from it, and, second, the specific character of chance and causality involved, or of their interplay. There may be many variations on how new formations, such as new species, in the biological evolution may arise or are destroyed. As I have stressed throughout, “expanded evolutionary theory” conceived by Gould, is defined by the great complexity of these relations, and we might need a greater complexity still.
The Romantics, such as Hölderlin, Kleist, Keats, and Shelley would, in Shelley’s words, “take the darker side” (Julian and Maddalo 49), and bring us at least to the threshold of nonclassical chance. Gould places Darwin between the Enlightenment and Romanticism, with the help of his grandfather Erasmus (much revered by Darwin), who, I would add, was an important and often equally revered figure for both traditions, and especially for Shelley (SET 595). Shelley’s The Triumph of Life, which presents a tragic-triumphant procession of life or/as death (it is true, of human life) that is hardly a pageant (which Gould favors) stops, remarkably, on an as-yet unanswered question: “What is Life?” (The Triumph of Life 544). The poem intimates that all life, biological or other, may be shaped and even ultimately governed by nonclassical chance. While remarkable, it is not by chance, given Shelley’s biography, and specifically his interest in contemporary science. Mary Shelley’s Frankenstein, for which Shelley wrote a preface, is shaped by the spectrum of scientific themes shared with Shelley’s work, and by this question “What is Life?”. Gould mentions the novel, via Shakespeare’s famous lines–“Nothing in him that doth fade/But does suffer a sea-change/Into something rich and strange”–from The Tempest (I.ii.401-03), the work multiply connected with Shelley’s work, including The Triumph of Life. Gould, at least at this juncture, takes a more positive view, as does Mary Shelley. Shakespeare’s lines, Gould reminds us, “appear on the tombstone of the great poet Percy Bysshe Shelley (also the author of the preface to his wife’s novella, Frankenstein, which cites Erasmus Darwin in its first line of text). I believe that these words would suit, and honor, Charles Darwin just as well and just as rightly” (SET 24). These words, it may be added, also offer as good a description as any of evolutionary change. There is, however, a darker side, along with “grandeur” to Darwin’s “view of life,” to cite the conclusion of The Origin of Species, the side that brings his view of life as life-death and of chance closer to Shelley’s in The Triumph of Life. In Paul de Man’s words, “The Triumph of Life warns us that, nothing, whether deed, word, thought or text, ever happens in relation, positive or negative, to anything that preceded, follows, or exists elsewhere, but only as a random event whose power, like the power of death, is due to the randomness of its occurrence” (122; emphasis added). De Man also stresses, however, that, while it retains the underlying overall economy of chance, thus reversing the classical view (where causality underlies chance), Shelley’s poem also teaches us that causal sequences do shape certain events. It also tells us how we may integrate irreducibly random events into classical-like causal sequences, which we often continue to prefer, as Gould noted above, but which may not be rigorously possible.
Nonclassical chance, then, is irreducible to any causality or necessity, not only in practice but, at the limit, also, and most fundamentally, in principle. There is no argumentation offered and there may be none in principle available to us that would allow us to eliminate chance and replace it with the picture of causality or necessity behind it. Nor, however, does one or, again, at the limit, can one postulate a causal dynamics as unknown or even unknowable but existing behind random events. This qualification is crucial. For, as I explained, some forms of the classical understanding of chance allow for and are defined by this type of assumption. The nonclassical chance is irreducibly random.
At the very least, it is irreducibly random within the field demarcated by a given theory, as in the evolutionary theory of Darwin and Gould, where random events in question may result from some exterior causality, as against quantum mechanics where all events in question in the theory are nonclassically random and are, thus, within the domain of the theory. Unlike in Milton and Pope, in Gould’s theory one is not concerned with the ultimate theological determination of the world (classical, by definition), but only with the specific scientific explanations of evolutionary dynamics. For example, one is not concerned with who or what arranged for the asteroid to hit the earth 65 or so millions years ago (seconds on the cosmological scale, and we, as a species, have been or will be around much less) or other catastrophes that punctuated and changed evolution. One is only concerned with how such events shape the workings of evolution. As I said, more generally, if a given punctuation or mutation has a causality behind it, this causality would not be linked to the evolutionarycausality/iesinitiated or affected by this punctuation or mutation. One might say that mutation, too, functions as a form of punctuation in this sense, although within a more gradual rather than catastrophically ruptured dynamics. One could be concerned with the causalities of such events in studying the motion of asteroids, subject to classical mechanics or else chaos theory. Understanding the specific nature of their motion is essential, for example, if we want to prevent, if we can, yet another chance event that would catastrophically change the course of evolution and would eliminate us from the face of the earth, would do us in, as it did the dinosaurs. That, however, would entail shifting the theoretical context outside the domain of evolutionary theory. In sum, in Darwin’s or Gould’s theories, one theoretically deals with causalities triggered by certain random events, such as mutations or punctuations, rather than with these events themselves in their own history, whether the latter is classical or nonclassical. In other words, evolutionary contingency in Darwin’s and Gould’s sense depends on the nonclassicality of interrupting or punctuating events shaping causal sequences the theory considered in a classical, and specifically descriptive way, just as classical physics does in considering its objects.
By contrast, in quantum theory, at least in certain (nonclassical) interpretations of it, we deal only with nonclassically shaped events, as opposed to causal (classical) chains that such events would trigger, as they may, for example, by virtue of their impact in the macroworld, to which chains we can, then, apply classical physics. Quantum theory is, accordingly, a theory of predicting such events on the basis of other events of the same type, without explaining (which may not be possible) the process leading from one event to another. If one wants a contrast to Gould’s or Darwin’s theory, quantum theory qua in principle7
Now, the question is whether the structure of evolutionary theory involves this type of nonclassical stratum as well–an unanswered or perhaps, in this form, unasked question of Gould’s book. Before I sketch my reasons for asking this question, or rather by way of transition, I would like to respond to the question that one might ask concerning my general argument here on classical vs. nonclassical chance, whether the latter is of a Gouldian (or Darwinian) type or of a more radical quantum-mechanical type. This question goes as follows. If the underlying causal dynamics of chance, while presupposed, could not be known even in the classical case, what difference would the introduction of nonclassical chance, that is, a suspension of even an assumption of causality behind chance, make? Can assuming something that we cannot possibly know make a difference? Indeed, as explained above, on Gould’s or Darwin’s view it would not make that significant a difference, since evolutionary theory does not deal with chance events themselves but only with their effects, which are causal sequences, treated classically. (The introduction itself of such events is, again, crucial for the structure of evolutionary theory.) Strange as it may seem, however, it can make a difference. We know that, in view of the so-called Bell’s theorem, it does make a difference in quantum theory. For the correctness of our theoretical prediction of the outcomes of the experiments depends on making or not making this assumption. In the words of quantum physicist David Mermin,
Bell [...] demonstrated that there were circumstances under which one could [in fact] settle a question of whether "something [a causal reality behind quantum randomness] one cannot know anything about exists all the same" [or not], and if quantum mechanics was quantitatively correct in its predictions, the answer was, contrary to Einstein's conviction, that it does not. (124)
By contrast, for classical statistical physics or, differently, chaos theory and complexity theory to be correct in their predictions, we must presuppose an underlying causal reality within the scope of the theory, even though we cannot, even in principle, access it.
Accordingly, one might argue that, whenever we deal with a theory where chance plays an essential role, the classical or conversely nonclassical nature of this chance may prove to be significant. Evolutionary theory is such a theory. A certain nonclassicality is already introduced into it by Darwin and extended by Gould (although the extension is subject of much debate among evolutionary theorists). This may be as much nonclassicality as Gould wants, and Gould’s macroevoluationary theory, defined by hierarchy, punctuation, spandrels, and so forth may not need more, although his general appeal of integrating contingency and (causal) general theory may leave space for more. Gould does not, however, here or, as far as I know, anywhere, discuss chance and contingency of the type we encounter in quantum theory or offer theoretical arguments of this (nonclassical) type. On the other hand, microevolutionary dynamics may require a kind of through-and-through quantum-mechanical nonclassicality. Such may be the case, for example, if one wants to address theoretically the nature of random mutations as part of evolutionary theory, rather than see them as microtransformations or micropunctuations, whose biology is bracketed by the evolutionary theory, either Darwinian or Gouldian (which incorporates Darwin on this score). At most, it appears to be left to other theoretical fields such as genetics, say, at the level of the molecular biology and chemistry and physics it involves, apart from evolutionary theory. If, however, as Gould argues in the passage cited earlier, “random” mutations are not necessarily “equally likely in all directions,” and if we want to understand how mutational dice are loaded (quantum dice, we recall, are) and make this understanding part of evolutionary theory, then the nature of such processes may be in question, possibly involving nonclassical features of the kind one finds in quantum theory. In the latter case, we would confront epistemological complexities, as concerns the possibility or impossibility of describing or explaining this type of process, of the type we encounter in quantum theory. There is a crucial difference. In quantum mechanics we deal primarily with predictions concerning future events on the basis of certain events that have previously occurred. By contrast, in evolutionary theory, at least so far, we deal with past events, whose “history” to some previous events we might want to trace, in however limited a fashion, which situation may lead to yet further theoretical complexities. The considerations of the kind just outlined may also arise in other interactions forming Gould’s “expansion of Darwin’s reliance upon organismal selection into a hierarchical model of simultaneous selection at several levels of Darwinian individuality (gene, cell lineage, organism, deme, species and clade)” (1340).
What would such a theory be? Would it be a theory of the quantum-mechanical type, for example, or would it still proceed along the lines of Darwin’s or Gould’s view of contingency on a smaller scale?8 Whether such a “unified” theory is possible is yet another question, to which I shall return presently. It is not unlike the question of a possible or impossible ultimate unified theory in physics, which would unify quantum theory, as a microlevel theory, and general relativity, as currently a macrolevel theory, within a single theory, a string theory, for example. Gould does not address these questions, although it may be seen as shadowing his argument, for example, in some of his discussions of genetic aspects of evolution and debates surrounding them.
Gould, unavoidably, invokes classical physics, via the works of d’Arcy Thomson, whose work, especially his famous On Growth and Form, pioneered a rigorous application of classical physics and related mathematics to biological morphology, as Gould discusses in some detail (SET 1182-1214). Gould might have mentioned the related morphological work of a great mathematician and d’Arcy Thomson’s fellow Aristotelian, René Thom (the two last names also share a signifier, a “form”), whom Gould only invokes in a related context of catastrophe theories, one of Thom’s great contribution to mathematics (922). Gould also discusses the more recent work of Stuart Kauffman in complexity theory, of which Kauffman was one of the pioneers, and which continues d’Arcy Thomson’s tradition of relating physics and biology and extends to new but classical theories, on the present definition, although not in Kaufmann’s terminology. As explained above, there are differences between classical physics, including classical statistical physics, and chaos and complexity theories, which compel Kaufmann to juxtapose them.9 Interestingly enough, however, especially given the place of contingency in Gould’s thinking, quantum theory, a paradigmatic and paradigmatically modern or indeed postmodern theory of chance, does not find its place in the book. The work in molecular biology, essential to modern genetics, stemming in part from quantum theory and in part initiated by quantum theorists, beginning with Erwin Schrödinger’s book What is Life?, which thus repeats Shelley’s question, is not part of the book either. But then, as I said, no book, however long, is ever long enough.
As I argue here, however, Gould’s contingency has crucial nonclassical affinities with quantum theory, and he could not avoid quantum theory altogether, at least by implication. One of the more remarkable junctures of personal, historical, philosophical, and scientific trajectories defining the book occurs around the case of the so-called “quantum evolution” theory (introduced in the 1940s). The name is an inevitably evocative title or, one might say, signifier. I do not want to overstress the significance of this signifier, especially given that the signified behind it is far from the (micro)considerationsof the quantum-theoretical type here discussed. It is in fact closer to Gould’s macroevolutionary theory, and this is why Gould discusses it. Moreover, as Gould shows (which is one of his points), quantum evolution theory progressed from its more radical to its more conventional form, maintaining the same terms or signifiers but subtly shifting its concepts (SET 521-531). Nevertheless, it is not out of place to speak of a shadow of the quantum over Gould’s argument and evolutionary theory, or conversely the shadow of Darwin, arguably the first step toward the nonclassical view of chance in science, over quantum theory. (There are also actual historical lineages and influences.)
One can, then, sum up the preceding argument as follows. First, the structure of evolutionary theory is fundamentally determined by whether we assume that the character of chance that shapes the contingencies of evolution is classical or nonclassical, or combines both, which, I would argue with Gould, is in fact the case, even given the more limited, Gouldian or Darwinian, form of nonclassicality. Second, the nature and the structure of evolutionary theory, arguably more so than that of any other single scientific theory, requires a maximal and multilevel deployment of both views and of their many combinations. In paradigmatic terms of physical theories, it needs the structures of causality and chance, and of their interplay, contingency, on the model of classical physics at some junctures; on the model of classical statistical physics at others; on the model of chaos and complexity theory at still others; and possibly (as we have only seen intimations of it so far) on still other models, such as those of quantum theory (which has different levels and versions in turn). The deployment of such models in evolutionary theory may be qualitative or quantitative, mathematical or nonmathematical, and so forth. But evolutionary theory may also need its own models, such as Darwin’s or Gould’s. Accordingly, it may demand from us the ultimate complexity in the domain of natural science and already engages this type of complexity. This is, I would argue, what Gould’s book teaches us, or this is how it answers or rather asks Shelley’s question “What is Life?”
But would it be, could it be one evolutionary theory, then, even with multiple structures, and in what sense of oneness? Gould appears to suggest or wants to see it as possibly a single theory. His commentary in his epilogue on Darwin’s famous passage ending The Origin of Species is of some interest in this respect. To cite Darwin’s great final sentence first:
There is grandeur to this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved. (490)
Gould turns this sentence around and turns around it, in a kind of mutual dance, a few times in his epilogue, beginning with this elegant turn:
Note how Darwin contrasts the dull repetitiveness of planetary cycling (despite the elegance and simplicity of its quantitative expression) with the gutsy glory of rich diversity of life's ever rising and expanding tree. Darwin even gives his metaphor a geometric flavor, as he contrasts the horizontal solar system, its planets cycling around a central sun to nowhere, with the vertical tree of life, starting in utmost simplicity at the bottom, and rising right through the horizontality of this repetitive physical setting towards the heavenly heights of magnificent and ever expanding diversity, in a contingent and unpredictable future of still greater possibility. (SET 1334)
Perhaps! The “utmost simplicity” at bottom only appears at the expense of the contingent event of enormous complexity, that is the origin of life, which, it is true, is properly bracketed in Darwin’s and Gould’s theories alike, but need not be, and no longer is, seen in terms of absolute origins. The future is far less certain, too. We also know (it is true, better than Darwin did) how complex the structure (more likely chaos) of the solar system is, let alone the nature, so far unfathomable, of gravitation, thanks to Einstein’s theory. I am of course not aiming these arguments against Darwin, who could not know them, or indeed against Gould, who is well aware of them. Besides, Gould’s main point here is a historical particularity, contingency, of Darwin’s view of life, as opposed to other possible views, to which I shall return presently. For the moment, I want to look at the image and indeed the concept of the tree–the tree of life and the tree of evolutionary theory–as governing Darwin and, via the image of Scilla’s coral, Gould’s view of both life itself and evolutionary theory. The tree of life (one would expect this) appears in the final sentence of Gould’s book as well. Even as it maps a radical revision of Darwin, this “vertical” view of evolutionary theory still implies a certain unifying attitude, whereby theories or sub-theories branch from a single ultimate lineage, without (ever?) leaving the tree and its hierarchy behind. Could it be the case even within evolutionary theory? Is it not possible to think of a different theoretical structure here (or, as I said, in physics as well) whereby we have a certain “horizontal” field of theories, interactive but not genealogically linked as branches within a single tree, theories that are heterogeneously interactive and interactively heterogeneous? This view may even be necessary if we want to pursue “the generation of theories appropriate to the characteristic rates and modalities of time’s higher tiers to explain the extensive range of macroevolutionary phenomena,” on which Gould insists (1340).
Gilles Deleuze and Felix Guattari would speak of “rhizome,” which they juxtapose to “tree,” although they, correctly, acknowledge that we need both types of structuration. Rhizome may still be too connected. Horizontality, however, and the suspension of any ultimate hierarchy are crucial. One could think in particular of the extraordinary Chapter 3, “10,000. B.C.: The Geology of Morals (Who Does the Earth Think It Is?),” of A Thousand Plateaus, the book that also offers a correlatively rhizomatic philosophy of history (39-74). The title obviously alludes to Nietzsche’s On the Genealogy of Morals, so crucial to Gould but perhaps not followed by him to its ultimate Nietzschean limits, including on this point, that of heterogeneous, if interactive, genealogies of and relationships between different theories or different practices of morality. But the chapter explores, naturally, in philosophical, rather than scientific, terms and in an allegorical mode, the structure of–among others–evolutionary theory, including its relation to the geological and cosmological forces that shaped it. (It also contains an ironic play upon the title of Darwin’s Descent of Man.) In the process it also suggests that this structure may take the horizontal, rhizomatic, theoretical field. I can, however, only indicate this problematic here. To properly address it would require the scale of Deleuze and Guattari’s A Thousand Plateaus (about 600 pages), if not of Gould’s book. Instead, I would like to close by returning, with Gould, to contingency.
Gould adds an epilogue to his epilogue, on contingency in literature vs. science, thus finally ending his “interminable book” on a triple synthesis–philosophical, scientific, and cultural–of causality and chance, of two types of evolutionary theory, and, finally (and not coincidentally, only contingently), of science and literature, all of which are represented in Darwin’s work and life (1342-43). The subject, in all three of its aspects, is implicitly linked to a slightly earlier discussion of Darwin’s “tree of life” and Kauffman’s critique of it from complexity theory, on contingency in immanent and narrative style of explanations and modes of knowing correlative to them, and then to the discussion of contingency in history and biography (1335-37, 1338-39). Now Gould “risks” (chances) “a final statement about contingency”:
And yet, as an epilog to this epilog and, honest to God, a true end to this interminable book, I risk a final statement about contingency, both to explicate the appeal of this subject, and to permit a recursion to my starting point in the most remarkable person and career of Charles Robert Darwin. Although contingency has been consistently underrated (or even unacknowledged) in stereotypical descriptions of scientific practice, the same subject remains a perennial favorite among literary folk, from the most snootily arcane to the most vigorously vernacular--and it behooves us to ask why. (1340)
It is at this juncture that Gould invokes Brontë’s Wuthering Heights (1340). It is a pity that in his first example of Tolstoy’s War and Peace, Gould, while correct in his argument, makes a technical error. Tolstoy does indeed argue, as Gould says, that “Napoleon’s defeat in Moscow in 1812 rested upon a thicket of apparently inconsequential and independent details, and not upon any broad and abstract claim about the souls of nations or the predictable efficacy of Russia’s two greatest generals, November and December” (1340). I would contend that it rested on both, as the predictable evolution of the French campaign was also “punctuated” by the generals in question, while Brontë’s or earlier Stendhal’s (a key precursor of Tolstoy, not mentioned by Gould) would be closer to the quantum-mechanical view of chance. (Actually one finds both conceptions in Stendhal.) In any event, Tolstoy does not argue this in “both prefaces,” as Gould mistakenly says, but in both of his epilogues, just as Gould himself does–a missed chance by Gould.
Gould’s own answer to his question is roughly that literature or art aims at the extraordinary, even in the ordinary, which could only be contingent and even singular, unique. Phenomena like Darwin or Newton, and their work and writings, are in the same category, as are certain phenomena in science itself. Gould says:
We care for the same reasons we love okapis, delight in the fossil evidence of trilobites, and mourn the passage of the dodo. We care because the broad events that had to happen, happened to happen in a certain particular way. And something almost unspeakably holy--I don't know how else to say this--underlies our discovery and confirmation of the actual details that made our world and also, in realms of contingency, assured the minutiae of its construction in the manner we know, and not in any one of a trillion other ways, nearly all of which would not have included the evolution of a scribe to record the beauty, the cruelty, the fascination, and the mystery. (1342)
He adds: “no difference truly separates science and art in this crucial respect. We only perceive a division because our disparate traditions lead us to focus upon different scales of identity” (1343). More specifically, the situation, according to Gould, is as follows. A different history of evolutionary theory or of physics (Newton is mentioned next, by way of the fact that Darwin is buried next to him in the Westminster Abbey), without Darwin or Newton, would be unlikely to change our theories of either physical nature or evolution. (To follow Gould’s view of biological evolution, the contingencies of the macroevolution of culture could do so, since they could deprive or relieve us of science, or of art, altogether.) This different history would, however, change our experience of either science or the history of both, in their particulars, as against those particulars that the work of Newton or that of Darwin brought into them. “We would [still] be enjoying an evolutionary view of life, but not the specific grandeur of ‘this [Darwin’s] view of life'” (1343). We would still be asking Shelley’s question “What is Life?,” but not in the way it is asked by Shelley’s poem, or by us after Shelley and Darwin, or both Darwins, Charles and Erasmus. Other particulars, perhaps equally grand, would take their place. Gould undoubtedly knew full well that this argument equally applies to his book, or his particular way of asking this question, Shelley’s and Darwin’s, the question of art and the question of science, and now (it’s been for a while, actually) Gould’s, “What is Life?.” Or, again, doubling the question mark, how do we ask this question, “What is Life?”?
Notes
1. “Spandrel” and “exaptation” are Gould’s key concepts developed in this central chapter (1214-95).
2. Other interactive conceptual pairs or more multiple clusters, such as, and especially, unity and multiplicity, or general and particular, are significant as well and could be correlated with the problematics in question.
3. Democritus appears to speak of necessity, as (with Democritus in mind) does Monod, which is not quite the same as causality, and the difference is not without significance in the present context. I shall, however, leave the subject aside here, and use primarily causality, and only invoke necessity on a few occasions.
4. I follow Hermann Weyl’s formulation of the principle in his discussion of Riemann in his classic, Space, Time, Matter (92).
5. This is a major theme throughout Derrida’s work, whose connections to evolutionary conceptuality are yet (thirty years in waiting) to be explored.
6. These events may involve statistical correlations, but without causal connections between the events themselves.
7. I cannot enter here into a detailed treatment of quantum theory and instead permit myself to refer to my discussion of the subject in The Knowable and the Unknowable: Modern Science, Nonclassical Theory, and the “Two Cultures” and references therein.
8. Were such transitions to involve quantum processes, as is sometimes conjectured, they would, at least in part, obey the quantum-mechanical model of chance, as sketched here.
9. It would not be possible to address Kauffman’s work here, in part in view of its technical complexity, although this work and complexity theory in general feature prominently in current discussions both in science and in the humanities and social sciences.
Works Cited
- Bohr, Niels. The Philosophical Writings of Niels Bohr. Vol. 2. Woodbridge, CT: Ox Bow P, 1987.
- de Man, Paul. The Rhetoric of Romanticism. New York: Columbia UP, 1984.
- Darwin, Charles. On the Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life. London: Murray, 1859.
- Deleuze, Gilles, and Felix Guattari. A Thousand Plateaus. Trans. Brian Massumi. Minneapolis: U of Minnesota P, 1987.
- Derrida, Jacques. Margins of Philosophy. Trans. Alan Bass. Chicago: U of Chicago P, 1982.
- Kuhn, Thomas. The Structure of Scientific Revolutions. Chicago: U of Chicago P, 1965.
- Mermin, N. David. Boojums All the Way Through: Communicating Science is a Prosaic Age. Cambridge: Cambridge UP, 1990.
- Nietzsche, Friedrich. The Gay Science. Trans. Walter Kaufmann. New York: Vintage, 1974.
- —. On the Genealogy of Morals and Ecce Homo. Trans. Walter Kaufmann. New York: Vintage, 1989.
- Plotnitsky, Arkady. The Knowable and the Unknowable: Modern Science, Nonclassical Theory, and the “Two Cultures.” Ann Arbor, MI: U of Michigan P, 2002.
- Weyl, Hermann. Space, Time, Matter. Trans. Henry L. Brose. New York: Dover, 1952.