A scientific explanatory project, part-whole explanation, and a kind of science, part-whole science are premised on identifying, investigating, and using parts and wholes. In the biological sciences, mechanistic, structuralist, and historical explanations are part-whole explanations. Each expresses different norms, explananda, and aims. Each is associated with a distinct partitioning frame for abstracting kinds of parts. These three explanatory projects can be complemented in order to provide an integrative vision of the whole system, as is shown for a detailed case study: (...) the tetrapod limb. My diagnosis of part-whole explanation in the biological sciences as well as in other domains exploring evolved, complex, and integrated systems (e.g., psychology and cognitive science) cross-cuts standard philosophical categories of explanation: causal explanation and explanation as unification. Part-whole explanation is itself one essential aspect of part-whole science. (shrink)

This inaugural handbook documents the distinctive research field that utilizes history and philosophy in investigation of theoretical, curricular and pedagogical issues in the teaching of science and mathematics. It is contributed to by 130 researchers from 30 countries; it provides a logically structured, fully referenced guide to the ways in which science and mathematics education is, informed by the history and philosophy of these disciplines, as well as by the philosophy of education more generally. The first handbook to cover the (...) field, it lays down a much-needed marker of progress to date and provides a platform for informed and coherent future analysis and research of the subject. -/- The publication comes at a time of heightened worldwide concern over the standard of science and mathematics education, attended by fierce debate over how best to reform curricula and enliven student engagement in the subjects There is a growing recognition among educators and policy makers that the learning of science must dovetail with learning about science; this handbook is uniquely positioned as a locus for the discussion. -/- The handbook features sections on pedagogical, theoretical, national, and biographical research, setting the literature of each tradition in its historical context. Each chapter engages in an assessment of the strengths and weakness of the research addressed, and suggests potentially fruitful avenues of future research. A key element of the handbook’s broader analytical framework is its identification and examination of unnoticed philosophical assumptions in science and mathematics research. It reminds readers at a crucial juncture that there has been a long and rich tradition of historical and philosophical engagements with science and mathematics teaching, and that lessons can be learnt from these engagements for the resolution of current theoretical, curricular and pedagogical questions that face teachers and administrators. (shrink)

A number of areas of biology raise questions about what is of value in the natural environment and how we ought to behave towards it: conservation biology, environmental science, and ecology, to name a few. Based on my experience teaching students from these and similar majors, I argue that the field of environmental ethics has much to teach these students. They come to me with pent-up questions and a feeling that more is needed to fully engage in their subjects, and (...) I believe some exposure to environmental ethics can help focus their interests and goals. I identify three primary areas in which environmental ethics can con- tribute to their education. The first is an examination of who (or what) should be considered to be part of our moral community (i.e., the community to whom we owe direct duties). Is it humans only? Or does it include all sentient life? Or all life? Or ecosystems considered holistically? Often, readings implicitly assume one or more of these answers; the goal is to make the student more sensitive to these implicit claims and to get them to think about the different reasons that support them. The second area, related to the first, is the application of the different answers concerning the extent of the ethical community to real environmental issues and problems. Students need to be aware of how the different answers concerning the moral community can imply conflicting answers for how we should act in certain cases and to think about ways to move toward conflict resolution. The third area in which environmental ethics can contribute is a more conceptual one, focusing on central concepts such as biodiversity, sustainability, species, and ecosystems. Exploring and evaluating various meanings of these terms will make students more reflective and thoughtful citizens and biologists, sensitive to the implications that different conceptual choices make. (shrink)

The explanatory role of natural selection is one of the long-term debates in evolutionary biology. Nevertheless, the consensus has been slippery because conceptual confusions and the absence of a unified, formal causal model that integrates different explanatory scopes of natural selection. In this study we attempt to examine two questions: (i) What can the theory of natural selection explain? and (ii) Is there a causal or explanatory model that integrates all natural selection explananda? For the first question, we argue that (...) five explananda have been assigned to the theory of natural selection and that four of them may be actually considered explananda of natural selection. For the second question, we claim that a probabilistic conception of causality and the statistical relevance concept of explanation are both good models for understanding the explanatory role of natural selection. We review the biological and philosophical disputes about the explanatory role of natural selection and formalize some explananda in probabilistic terms using classical results from population genetics. Most of these explananda have been discussed in philosophical terms but some of them have been mixed up and confused. We analyze and set the limits of these problems. (shrink)

Transhumanism is a means of advocating a re-engineering of conditions that surround human existence at both ends. The problem set before us in this chapter is to inquire into what determined its appearance, in particular in the humanism it seeks to overcome. We look at the spirit of overcoming itself, and the impatience with the Self, in order to try to understand why it seeks a saving power in technology. We then consider how the evolutionary account of the production of (...) organisms does not set them against a perfect standard, but rather injects in them a contingency that seems to be near to the heart of the problem. We then try to assess the objective basis for improvements and manipulation of nature, and although we do not find it forbidden on all occasions, it seems that the criteria for such alterations are impossible to detach from a form of eugenics. We finally open a window toward a theological account of the problem, and find that the desire of autonomy and independence is inevitably going to be challenged by the Christian dogma of creation. (shrink)

Abstract Is it plausible to claim (some) non?human animals have beliefs, on the (non?behaviourist) assumption that believing is or involves subjects? engaging in practical reasoning which takes account of meanings? Some answer Yes, on the ground that evolutionary continuities linking humans with other animals must include psychological ones. But (1) evolution does not operate?even primarily?by means of continuities. Thus species, no matter how closely related (in fact, sometimes even conspecifics) operate with very different adaptive ?tricks'; and it is plausible to (...) think these, rather than the physiological ?groundings? underlying them, are the best means of (analogies for) explaining beliefs. Also (2) it is reasonable to assimilate most cases ?down? to creatures (e.g. flies) that obviously lack beliefs rather than ?up? to others (chimpanzees) that apparently possess belief?like states (proto?beliefs), because observation shows the internal workings of such middle animals? ?beliefs? differ markedly from the corresponding things humans do. For example, ducks do not have beliefs about the numbers of objects, because although they estimate numerically, they do it in a way that is much more firmly connected to perceiving than would be the case either with counting or a counting?like process. (shrink)

(1993). Social Evolution: Paradigms and problems. World Futures: Vol. 38, Theoretical Achievements and Practical Applications of General Evolutionary Theory, pp. 1-16.

Nobel-price winning atmospheric chemist Paul Crutzen introduced in 2000 the concept of the Anthropocene as the name for the successor geological period to the Holocene. The Holocene started about 12,000 years ago and is characterized by the relatively stable and temperate climatic and environmental conditions that were conducive to the development of human societies. Until recently, human development had relatively little impact on the dynamics of geological time. Although disagreement exists over the exact birth date of the Anthropocene, it is (...) indisputable that the impact of human activity on the geo-climatic environment became more pronounced from the industrial revolution onwards, leading to a situation in which humans are now widely considered to have an eco-geologically critical impact on the earth's bio-physical system. The most obvious example is the accumulation of greenhouse gases like CO2and Methane (CH4) in the atmosphere and the changes this induces in climatic dynamics. Others are the growing homogenization of biodiversity as a result of human-induced species migration, mass extinction and bio-diversity loss, the manufacturing of new (sub-)species through genetic modification, or the geodetic consequences resulting from, for example, large dam construction, mining and changing sea-levels. (shrink)

Philosophers have used the probabilistic relation of ’screening-off‘ to explicate concepts in the theories of causation and explanation. Brandon has used screening-off relations in an attempt to reconstruct an argument of Mayr and Gould that natural selection acts at the level of the organism. I argue that Brandon‘s reconstruction is unsuccessful.

This book is about experiential content: what it is; what kind of account can be given of it. I am concerned with identifying and attacking one main view - I call it the inferentialist proposal. This account is central to the philosophy of mind, epistemology and philosophy of science and perception. I claim, however, that it needs to be recast into something far more subtle and enriched, and I attempt to provide a better alternative in these pages. The inferentialist proposal (...) holds that experiential content is necessarily under¬pinned by sophisticated cognitive influences. My alternative, the continuum theory, holds that these influences are relevant to experience only at certain levels of organisation and that at other levels there are contents which such features do not capture at all. Central to my account is that there are degrees to which cognitive influences affect experiential content; indeed, for the most part, experience is an amalgam of both inferential and non-inferential features. I claim that the inferentialist proposal is fundamentally flawed and deserves replacement, and I argue that my alternative fills the hollow that remains. The book is divided into four sections. In Part I, Chapter 1, I introduce two traditionally rival views of experiential content. In Chapter 2, I develop my continuum alternative. Chapter 3 assesses the relationship between experience and language, while Chapter 4 explores the relationship between beliefs and experience. The overall argument is that it has been a mistake to understand experience simply in inferential or non-inferential terms. In Part II, I examine the structure of mental content. Chapter 5 is concerned with the kinds of experiences which escape the inferentialist analysis. Chapter 6 considers Kant’s metaphysic of experience counterpointed to Lorenz’s reading of his work in the light of evolutionary biology. Chapter 7 treats animal experience in relation to the continuum view I am developing, while Chapter 8 reviews Fodor’s contribution to perceptual psychology. It is argued that the view of experiential content being developed is both consistent with empirical data on informationally local perceptual sub-systems, but also accords well with evolutionary theory and a naturalist interpretation of Kant’s taxonomy. Part III deals with inferentialism in the philosophy of science. In Chapter 9, I assess the theory dependence of observation thesis as it is advanced by Paul Feyerabend. I bring out of his account a subtle confusion concerning the importance of inference in the context of scientific inquiry. Part IV deals with the issue of experience in the philosophy of mind. In Chapter 10, I look at Wilfred Sellars’s attack on sense data theories. Chapter 11 confronts Paul Churchland’s treatment of ‘folk psychology’ while Chapter 12 isolates the issue of experiential qualia and the position of property dualism. I offer a critical review of Thomas Nagel’s work in this chapter and claim that his position can be read in a way which is consistent with the continuum account I am developing. I conclude the book in the usual fashion with a summary of the central claims. (shrink)

No response that was not as long and intricate as the two commentaries combined could do justice to their details, so what follows will satisfy nobody, myself included. I will concentrate on one issue discussed by both commentators: the relationship between evolution and teleological (or intentional) explanation. My response, in its brevity, may have just one virtue: it will confirm some of the hunches (or should I say suspicions) that these and other writers have entertained about my views. For more (...) closely argued defenses of my points, see Dennett 1990a,b,c; 1991a,b. (shrink)

Abstract One of the most important things that the Darwinian revolution affected is the previous teleological thinking. In particular, the attribution of functions to various entities of the natural world with explanatory pretensions. In this change, his theory of natural selection played an important role. We all agree on that, but the diversity and heterogeneity of the answers that try to explain what Darwin did exactly with functional biology are overwhelming. In this paper I will try to show how Darwin (...) modified previous functional biology. Pre-Darwinian naturalists did not hesitate to attribute functions in which, for example, the traits of one species were in the service of other species. I will try to show that this has consequences on the discussion regarding the nature of functional language, since the main approaches, the systemic and the etiological, do not adequately account for these changes and therefore do not account for the way functional biology regulates the kind of legitimate functions. I will outline a possible new solution to this problem: appropriate functional attributions in Darwinian functional biology could be regulated by a theory or a set of laws that provide the criteria for determining its fundamental concepts. -/- Resumen: Una de las cosas más importantes a las que la revolución darwiniana afectó es el pensamiento teleológico previo. En particular, la atribución de funciones a diversas entidades del mundo natural con pretensiones explicativas. En este cambio, su teoría de la selección natural desempeñó un papel importante. Todos estamos de acuerdo en ello, pero la diversidad y heterogeneidad de las respuestas que tratan de explicar lo que Darwin hizo exactamente con la biología funcional son abrumadoras. En este artículo intentaré mostrar cómo Darwin modificó la biología funcional anterior. Los naturalistas predarwinianos no dudaban en atribuir funciones en las que, por ejemplo, los rasgos de una especie estaban al servicio de otras especies. Intentaré mostrar que esto tiene consecuencias en la discusión sobre la naturaleza del lenguaje funcional, pues los principales enfoques, el sistémico y el etiológico, no dan cuenta adecuadamente de estos cambios y, por tanto, no dan cuenta de la forma en que la biología funcional regula el tipo de funciones legítimas. Esbozaré una posible nueva solución a este problema: las atribuciones funcionales apropiadas en la biología funcional darwiniana podrían estar reguladas por una teoría o un conjunto de leyes que proporcionen los criterios para determinar sus conceptos fundamentales. -/- . (shrink)

The standard perception of the dichotomy between population thinking and essentialism (typological thinking) in evolutionary economics descends from the golden age of the neo-Darwinian Synthesis. Over the last few decades the received view on population thinking has been seriously challenged in biology and its philosophy. First, the strong version of population thinking that banishes essentialism witnessed important tensions stemming from the ontological status of species. These tensions have been amplified by the demise of positivism and the rise of a new (...) essentialism in philosophy of science. Second, the soft version that transforms the opposition between population thinking and essentialism to the dichotomy between ultimate and proximate causation has led to contradictory interpretations regarding the locus of ultimate causes. Taking stock of the previous discussion the paper addresses the limits to population thinking in the socio-economic realm. The upshot is that without denying the important achievements made by the application of population thinking in sub-disciplines like industrial dynamics and economic anthropology, the idea to generalize these applications into the whole socio-economic realm is problematic. The aforementioned achievements cannot come to grips with the structural aspects of capitalism, its different periods (e.g. the contemporary finance-led capitalism) and its geographical varieties. The resulting gap points to the importance of structural analysis (essentialism) and evolutionary political economy. The latter is distinguished from the rest of evolutionary economics by its project to go beyond the surface of economic phenomena and to critically analyze their underlying social structures. (shrink)

According to simulationism, the function of episodic memory is not to remember the past, but to help construct representations of possible future episodes, by drawing together features from different experiential sources. This article suggests that the relationship between the traditional storehouse view, on which the function of memory is remembering, and the simulationist approach is more complicated than has been typically acknowledged. This is attributed, in part, to incorrect interpretations of what remembering on the storehouse view requires. Further, by appeal (...) to function pluralism, the article questions both the assumption that the traditional view and simulationism are inconsistent, and the simulationist’s inference to the best explanation strategy that is based upon this assumption. The article then provides an evaluation of the simulationist argument against the traditional view, and finds it in need of further support. (shrink)

This thesis is about experiential content: what it is; what kind of account can be given of it. I am concerned with identifying and attacking one main view - I call it the inferentialist proposal. This account is central to the philosophy of mind, epistemology and philosophy of science and perception. I claim, however, that it needs to be recast into something far more subtle and enriched, and I attempt to provide a better alternative in these pages. The inferentialist proposal (...) holds that experiential content is necessarily under¬pinned by sophisticated cognitive influences. My alternative, the continuum theory, holds that these influences are relevant to experience only at certain levels of organisation and that at other levels there are contents which such features do not capture at all. Central to my account is that there are degrees to which cognitive influences affect experiential content; indeed, for the most part, experience is an amalgam of both inferential and non-inferential features. I claim that the inferentialist proposal is fundamentally flawed and deserves replacement, and I argue that my alternative fills the hollow that remains. The thesis is divided into four sections. In Part I, Chapter 1, I introduce two traditionally rival views of experiential content. In Chapter 2, I develop my continuum alternative. Chapter 3 assesses the relationship between experience and language, while Chapter 4 explores the relationship between beliefs and experience. The overall argument is that it has been a mistake to understand experience simply in inferential or non-inferential terms. In Part II, I examine the structure of mental content. Chapter 5 is concerned with the kinds of experiences which escape the inferentialist analysis. Chapter 6 considers Kant’s metaphysic of experience counterpointed to Lorenz’s reading of his work in the light of evolutionary biology. Chapter 7 treats animal experience in relation to the continuum view I am developing, while Chapter 8 reviews Fodor’s contribution to perceptual psychology. It is argued that the view of experiential content being developed is both consistent with empirical data on informationally local perceptual sub-systems, but also accords well with evolutionary theory and a naturalist interpretation of Kant’s taxonomy. Part III deals with inferentialism in the philosophy of science. In Chapter 9, I assess the theory dependence of observation thesis as it is advanced by Paul Feyerabend. I bring out of his account a subtle confusion concerning the importance of inference in the context of scientific inquiry. Part IV deals with the issue of experience in the philosophy of mind. In Chapter 10, I look at Wilfred Sellars’s attack on sense data theories. Chapter 11 confronts Paul Churchland’s treatment of ‘folk psychology’ while Chapter 12 isolates the issue of experiential qualia and the position of property dualism. I offer a critical review of Thomas Nagel’s work in this chapter and claim that his position can be read in a way which is consistent with the continuum account I am developing. I conclude the thesis in the usual fashion with a summary of the central claims. (shrink)

The problem of error is an old argument for atheism that can be found in Medieval and Early Modern Philosophy. Although it is not widely discussed in the contemporary literature in the Philosophy of Religion, I resurrect it and give it a modern spin. By relying on empirical studies in moral psychology that demonstrate that moral judgments from human beings are generally susceptible to certain psychological biases, such as framing and order effects, I claim that if God is responsible for (...) making human beings such that we have these biases, this means that God is not a perfect being. The findings in empirical moral psychology create a problem for the existence of God, traditionally conceived. (shrink)

The application of evolutionary ideas to socioeconomic systems has been an increasingly prominent theme in the work of Friedrich Hayek, and the motif has become dominant in his recent book. In an earlier issue of this journal, Viktor Vanberg raises two substantive criticisms of Friedrich Hayek' theory of cultural evolution that invoke some important questions concerning use of the evolutionary analogy in social science.

The concept of adaptation is employed in many fields such as biology, psychology, cognitive sciences, robotics, social sciences, even literacy and art,1 and its meaning varies quite evidently according to the particular research context in which it is applied. We expect to find a particularly rich catalogue of meanings within evolutionary biology, where adaptation has held a particularly central role since Darwin’s The Origin of Species (1859) throughout important epistemological shifts and scientific findings that enriched and diversified the concept. Accordingly, (...) a conceptual taxonomy of adaptation in evolutionary biology may help to disambiguate it. Interdisciplinary researches focused on adaptation would benefit from such a result. In the present work we recognize and define seven different meanings of adaptation: (1) individual fitness; (2) adaptation of a population; (3) adaptation as the process of natural selection; (4) adaptive traits; (5) molecular adaptation; (6) adaptation as structural tinkering; (7) plasticity. For convenience here, we refer to them as W-, P-, NS-, T-, M-, S- and PL-ADAPTATION. We present the seven meanings in some detail, hinting at their respective origins and conceptual developments in the history of evolutionary thought (references are offered for further deepening). However, it is important to point out that evolution researchers seldom if ever refer to a single meaning purified from the others. This applies also to the authors we cite as representatives of one of the seven meanings. In Discussion and Conclusion draw from our work some future perspectives for adaptation within evolutionary biology. (shrink)

A comment on Paul Schoemaker's target article in Behavioral and Brain Sciences, 14 (1991), p. 205-215, "The Quest for Optimality: A Positive Heuristic of Science?" (https://doi.org/10.1017/S0140525X00066140). This comment argues that the optimizing model of decision leads to an infinite regress, once internal costs of decision (i.e., information and computation costs) are duly taken into account.

. Despite the classical prohibition of moving from fact to value, encounter with the biodiversity and plenitude of being in evolutionary natural history moves us to respect life, even to reverence it. Darwinian accounts are value-laden and necessary for understanding life at the same time that Darwinian theory fails to provide sufficient cause for the historically developing diversity and increasing complexity on Earth. Earth is a providing ground; matter and energy on Earth support life, but distinctive to life is information (...) coded in the genetic molecules that superintends this matter-energy. Life is generated and regenerated in struggle, persists in its perishing. Such life is also a gift; nature is grace. Biologists and theologians join in celebrating and conserving the genesis on Earth, awed in their encounter with this creativity that characterizes our home planet. (shrink)

Through the last half of the nineteenth century and the first part of the twentieth, no scientist more vigorously defended Darwinian theory than the German Ernst Haeckel (1834–1919). More people learned of the new ideas through his voluminous publications, translated into numerous languages, than through any other source, including Darwin’s own writings. He enraged many of his contemporaries, especially among the religiously orthodox; and the enmity between evolutionary theory and religious fundamentalism that still burns brightly today may in large measure (...) be attributed to Haeckel’s unremitting attacks on the ingressions of religion into science. Though he retained a life-long friendship with and the support of Darwin, some in the scientific community who were critical of evolutionary theory—Emil Du Bois-Reymond, Rudolf Virchow, and Louis Agassiz, for instance—accused him of deception. That charge has been renewed in our time based on seemingly incontrovertible evidence. In a Science magazine article published in 1997, ‘‘Haeckel’s Embryos: Fraud Rediscovered,’’ Haeckel, was indicted of having intentionally misrepresented embryological development (Pennisi 1997). The article reported that the work of Michael Richardson and his colleagues demonstrated this malfeasance through a comparison of Haeckel’s illustrations of early-stage embryos with photographs of the same species at a comparable stage (see Fig. 1). The photos showed embryos of various species that differed among themselves and certainly from Haeckel’s images. The differences were striking and the implication obvious: fraudulent misrepresentation. Richardson, as quoted in the article, affirmed the charge: ‘‘It looks like it’s turning out to be one of the most famous fakes in biology’’. (shrink)

Welfare biology is the study of living things and their environment with respect to their welfare. Despite difficulties of ascertaining and measuring welfare and relevancy to normative issues, welfare biology is a positive science. Evolutionary economics and population dynamics are used to help answer basic questions in welfare biology : Which species are affective sentients capable of welfare? Do they enjoy positive or negative welfare? Can their welfare be dramatically increased? Under plausible axioms, all conscious species are plastic and all (...) plastic species are conscious. More complex niches favour the evolution of more rational species. Evolutionary economics also supports the common-sense view that individual sentients failing to survive to mate suffer negative welfare. A kind of God-made fairness between species is also unexpectedly found. The contrast between growth maximization, average welfare, and total welfare maximization is discussed. It is shown that welfare could be increased without even sacrificing numbers. Since the long-term reduction in animal suffering depends on scientific advances, strict restrictions on animal experimentation may be counter-productive to animal welfare. (shrink)

This article reviews two standard criticisms of creationism/intelligent design (ID): it is unfalsifiable, and it is refuted by the many imperfect adaptations found in nature. Problems with both criticisms are discussed. A conception of testability is described that avoids the defects in Karl Popper’s falsifiability criterion. Although ID comes in multiple forms, which call for different criticisms, it emerges that ID fails to constitute a serious alternative to evolutionary theory.

Many people have argued that the evolution of the human language faculty cannot be explained by Darwinian natural selection. Chomsky and Gould have suggested that language may have evolved as the by-product of selection for other abilities or as a consequence of as-yet unknown laws of growth and form. Others have argued that a biological specialization for grammar is incompatible with every tenet of Darwinian theory – that it shows no genetic variation, could not exist in any intermediate forms, confers (...) no selective advantage, and would require more evolutionary time and genomic space than is available. We examine these arguments and show that they depend on inaccurate assumptions about biology or language or both. Evolutionary theory offers clear criteria for when a trait should be attributed to natural selection: complex design for some function, and the absence of alternative processes capable of explaining such complexity. Human language meets these criteria: Grammar is a complex mechanism tailored to the transmission of propositional structures through a serial interface. Autonomous and arbitrary grammatical phenomena have been offered as counterexamples to the position that language is an adaptation, but this reasoning is unsound: Communication protocols depend on arbitrary conventions that are adaptive as long as they are shared. Consequently, language acquisition in the child should systematically differ from language evolution in the species, and attempts to analogize them are misleading. Reviewing other arguments and data, we conclude that there is every reason to believe that a specialization for grammar evolved by a conventional neo-Darwinian process. (shrink)

The human attempts to access, measure and organize physical phenomena have led to a manifold construction of mathematical and physical spaces. We will survey the evolution of geometries from Euclid to the Algebraic Geometry of the 20th century. The role of Persian/Arabic Algebra in this transition and its Western symbolic development is emphasized. In this relation, we will also discuss changes in the ontological attitudes toward mathematics and its applications. Historically, the encounter of geometric and algebraic perspectives enriched the mathematical (...) practices and their foundations. Yet, the collapse of Euclidean certitudes, of over 2300 years, and the crisis in the mathematical analysis of the 19th century, led to the exclusion of “geometric judgments” from the foundations of Mathematics. After the success and the limits of the logico-formal analysis, it is necessary to broaden our foundational tools and re-examine the interactions with natural sciences. In particular, the way the geometric and algebraic approaches organize knowledge is analyzed as a cross-disciplinary and cross-cultural issue and will be examined in Mathematical Physics and Biology. We finally discuss how the current notions of mathematical (phase) “space” should be revisited for the purposes of life sciences. (shrink)

‘There are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns—the ones we don’t know we don’t know.’ —Donald Rumsfeld, 2003, President George W. Bush’s Secretary of Defense, on the subject of the U.S. government’s failure to discover weapons of mass destruction in Iraq.