Few philosophers of science have influenced as many readers as Thomas S. Kuhn. Yet no comprehensive study of his ideas has existed--until now. In this volume, Paul Hoyningen-Huene examines Kuhn's work over four decades, from the days before The Structure of Scientific Revolutions to the present, and puts Kuhn's philosophical development in a historical framework. Scholars from disciplines as diverse as political science and art history have offered widely differing interpretations of Kuhn's ideas, appropriating his notions of paradigm shifts (...) and revolutions to fit their own theories, however imperfectly. Hoyningen-Huene does not merely offer another interpretation--he brings Kuhn's work into focus with rigorous philosophical analysis. Through extended discussions with Kuhn and an encyclopedic reading of his work, Hoyningen-Huene looks at the problems and justifications of his claims and determines how his theories might be expanded. Most significantly, he discovers that The Structure of Scientific Revolutions can be understood only with reference to the historiographic foundation of Kuhn's philosophy. Discussing the concepts of paradigms, paradigm shifts, normal science, and scientific revolutions, Hoyningen-Huene traces their evolution to Kuhn's experience as a historian of contemporary science. From here, Hoyningen-Huene examines Kuhn's well-known thesis that scientists on opposite sides of a revolutionary divide "work in different worlds," explaining Kuhn's notion of a world-change during a scientific revolution. He even considers Kuhn's most controversial claims--his attack on the distinction between the contexts of discovery and justification and his notion of incommensurability--addressing both criticisms and defenses of these ideas. Destined to become the authoritative philosophical study of Kuhn's work, Reconstructing Scientific Revolutions both enriches our understanding of Kuhn and provides powerful interpretive tools for bridging Continental and Anglo-American philosophical traditions. (shrink)

I argue for the merits of studying historical moral revolutions to inform moral and political philosophy. Such a research program is not merely of empirical, historical interest but has normative implications. To explain why, I situate the proposal in the tradition of naturalized epistemology. As Alison M. Jaggar and other scholars have argued, a naturalistic approach is characteristic of much feminist philosophy. Accordingly, I argue that the study of moral revolutions would be especially fruitful for feminist moral and (...) political philosophers. (shrink)

Note: Sections at a more advanced level are indicated by ∞. Preface ix Acknowledgments x Introduction 1 I Nicolaus Copernicus: The Loss of Centrality 3 1 Ptolemy and Copernicus 3 2 A Clash of Two Worldviews 4 2.1 The geocentric worldview 5 2.2 Aristotle’s cosmology 5 2.3 Ptolemy’s geocentrism 9 2.4 A philosophical aside: Outlook 14 2.5 Shaking the presuppositions: Some medieval developments 17 3 The Heliocentric Worldview 20 3.1 Nicolaus Copernicus 21 3.2 The explanation of the seasons 25 3.3 (...) Copernicus and the Copernican turn 28 3.3.1 A philosophical aside: From empirical adequacy to theoretical validity 32 3.4 Copernicus consolidated: Kepler and Galileo 32 4 Copernicus was not a Scientifi c Revolutionary 37 4.1 The Copernican method 39 4.2 The relativity of motion 42 5 The Transition to Newton 43 5.1 On hypotheses 45 6 Some Philosophical Lessons 47 6.1 The loss of centrality 48 6.2 Was Copernicus a realist? 51 6.2.1 Lessons for instrumentalism and realism 52 6.3 Modern realism 55 6.4 The underdetermination of theories by evidence 58 6.4.1 The Duhem--Quine thesis 59 ∞ 6.4.2 The power of constraints 61 ∞ 6.5 Theories, models, and laws 64 ∞ 6.5.1 Theories and models 64 ∞ 6.5.2 Laws of nature, laws of science 68 ∞ 6.5.3 Philosophical views of laws 69 ∞ 6.5.3.1 The inference view 69 ∞ 6.5.3.2 The regularity view 70 ∞ 6.5.3.3 The necessitarian view 73 ∞ 6.5.3.4 The structural view 75 7 Copernicus and Scientifi c Revolutions 77 8 The Anthropic Principle: A Reversal of the Copernican Turn? 83 Reading List 87 Essay Questions 91 II Charles Darwin: The Loss of Rational Design 93 1 Darwin and Copernicus 93 2 Views of Organic Life 94 2.1 Teleology 94 2.1.1 The Great Chain of Being 97 2.1.2 Design arguments 99 2.1.3 Jean Baptiste Lamarck 104 3 Fossil Discoveries 106 3.1 Of bones and skeletons 108 3.2 The antiquity of man 110 4 Darwin’s Revolution 112 4.1 The Darwinian view of life 114 4.1.1 Principles of evolution 116 4.2 The descent of man 119 5 Philosophical Matters 124 5.1 Philosophical presuppositions: Mechanical worldview, determinism, materialism 125 5.2 From biology to the philosophy of mind 129 5.2.1 Empiricism 129 5.2.2 Philosophy of mind 132 5.2.3 Emergent minds 134 5.3 The loss of rational design 136 5.4 Intelligent design 139 6 A Question of Method 143 6.1 Darwinian inferences 143 6.2 Philosophical empiricism 147 6.3 Some principles of elimination 149 ∞ 6.4 Essential features of eliminative induction 150 6.5 Falsifi ability or testability? 155 6.6 Explanation and prediction 157 ∞ 6.7 Some models of scientifi c explanation 159 ∞ 6.7.1 Hempel’s models 160 ∞ 6.7.2 Functional models 161 ∞ 6.7.3 Causal models 163 6.7.3.1 A counterfactual-interventionist account 163 6.7.3.2 A conditional model of causation 165 ∞ 6.7.4 Structural explanations 169 6.8 A brief return to realism 172 6.9 Darwin and scientifi c revolutions 174 6.9.1 Philosophical consequences 176 Reading List 177 Essay Questions 183 III Sigmund Freud: The Loss of Transparency 185 1 Copernicus, Darwin, and Freud 185 2 Some Views of Humankind 187 2.1 Enlightenment views of human nature 188 2.2 Nietzsche’s view of human nature 190 3 Scientism and the Freudian Model of Personality 191 3.1 Freud’s model of the mind 192 3.1.1 A summary of psychoanalytic theory 192 3.1.2 Analogy with physics 195 3.1.3 Freud as an Enlightenment thinker 200 3.1.4 The scientifi c status of the Freudian model 202 3.1.4.1 Freud’s methods 202 ∞ 3.1.4.2 The method of eliminative induction, again 205 3.1.5 Freud stands between the empirical and the hermeneutic models 208 3.1.6 The role of mind in the social world 209 4 The Social Sciences beyond Freud 210 4.1 Two standard models of the social sciences -- some history 210 4.1.1 The naturalistic model 211 4.1.2 The hermeneutic model 213 4.2 Essential features of social science models 218 4.2.1 Essential features of the naturalistic model 218 4.2.2 Essential features of the hermeneutic model 221 4.3 Questions of methodology 224 ∞ 4.3.1 What is Verstehen? 225 ∞ 4.3.2 Weber’s methodology of ideal types 229 ∞ 4.3.3 Verstehen and objectivity 234 ∞ 4.4 Causation in the social sciences 236 ∞ 4.4.1 Weber on causation 236 ∞ 4.4.2 On the existence of social laws 239 4.4.3 Explanation and prediction in the social sciences 242 4.4.4 Underdetermination 243 4.4.5 Realism and relativism 244 ∞ 4.4.6 Reductionism and functionalism 248 5 Evolution and the Social Sciences 253 5.1 Sociobiology -- the fourth revolution? 254 5.2 Evolutionary psychology 257 6 Freud and Revolutions in Thought 261 6.1 Revolutions in thought vs. revolutions in science 263 Reading List 263 Essay Questions 269 Name Index 271 Subject Index 274. (shrink)

Kuhn’s Structure of Scientific Revolutions is notable for the readiness with which it drew on the results of cognitive psychology. These naturalistic elements were not well received and Kuhn did not subsequently develop them in his pub- lished work. Nonetheless, in a philosophical climate more receptive to naturalism, we are able to give a more positive evaluation of Kuhn’s proposals. Recently, philosophers such as Nersessian, Nickles, Andersen, Barker, and Chen have used the results of work on case-based reasoning, analogical (...) thinking, dynamic frames, and the like to illuminate and develop various aspects of Kuhn’s thought in Structure. In particular this work aims to give depth to the Kuhnian concepts of a paradigm and incommensurability. I review this work and identify two broad strands of research. One emphasizes work on concepts; the other focusses on cognitive habits. After contrasting these, I argue that the conceptual strand fails to be a complete account of scientific revolutions. We need a broad approach that draws on a variety of resources in psychology and cognitive science. (shrink)

Thomas S. Kuhn's classic book is now available with a new index.

A scientific community cannot practice its trade without some set of received beliefs. These beliefs form the foundation of the "educational initiation that prepares and licenses the student for professional practice". The nature of the "rigorous and rigid" preparation helps ensure that the received beliefs are firmly fixed in the student's mind. Scientists take great pains to defend the assumption that scientists know what the world is like...To this end, "normal science" will often suppress novelties which undermine its foundations. Research (...) is therefore not about discovering the unknown, but rather "a strenuous and devoted attempt to force nature into the conceptual boxes supplied by professional education". (shrink)

A good book may have the power to change the way we see the world, but a great book actually becomes part of our daily consciousness, pervading our thinking to the point that we take it for granted, and we forget how provocative and challenging its ideas once were—and still are. _The Structure of Scientific Revolutions _is that kind of book. When it was first published in 1962, it was a landmark event in the history and philosophy of science. (...) Fifty years later, it still has many lessons to teach. With _The Structure of Scientific Revolutions, _Kuhn challenged long-standing linear notions of scientific progress, arguing that transformative ideas don’t arise from the day-to-day, gradual process of experimentation and data accumulation but that the revolutions in science, those breakthrough moments that disrupt accepted thinking and offer unanticipated ideas, occur outside of “normal science,” as he called it. Though Kuhn was writing when physics ruled the sciences, his ideas on how scientific revolutions bring order to the anomalies that amass over time in research experiments are still instructive in our biotech age. This new edition of Kuhn’s essential work in the history of science includes an insightful introduction by Ian Hacking, which clarifies terms popularized by Kuhn, including paradigm and incommensurability, and applies Kuhn’s ideas to the science of today. Usefully keyed to the separate sections of the book, Hacking’s introduction provides important background information as well as a contemporary context. Newly designed, with an expanded index, this edition will be eagerly welcomed by the next generation of readers seeking to understand the history of our perspectives on science. (shrink)

Bringing together important writings not easily available elsewhere, this volume provides a convenient and stimulating overview of recent work in the philosophy of science. The contributors include Paul Feyerabend, Ian Hacking, T.S. Kuhn, Imre Lakatos, Laurens Laudan, Karl Popper, Hilary Putnam, and Dudley Shapere. In addition, Hacking provides an introductory essay and a selective bibliography.

In the last few decades, several philosophers have written on the topic of moral revolutions, distinguishing them from other kinds of society-level moral change. This article surveys recent accounts of moral revolutions in moral philosophy. Different authors use quite different criteria to pick out moral revolutions. Features treated as relevant include radicality, depth or fundamentality, pervasiveness, novelty and particular causes. We also characterize the factors that have been proposed to cause moral revolutions, including anomalies in existing (...) moral codes, changing honour codes, art, economic conditions and individuals or groups. Finally, we discuss what accounts of moral revolutions have in common, how they differ and how moral revolutions are distinguished from other kinds of moral change, such as drift and reform. (shrink)

The last century saw two great revolutions in genetics the development of classic Mendelian theory and the discovery and investigation of DNA. Each fundamental scientific discovery in turn generated its own distinctive technology. These two case studies, examined in this text, enable the author to conduct a philosophical exploration of the relationship between fundamental scientific discoveries on the one hand, and the technologies that spring from them on the other. As such it is also an exercise in the philosophy (...) of technology. (shrink)

An historical survey of Thomas Kuhn's 1962 The Structure of Scientific Revolutions, charting the development of this influential work throughout Kuhn's career and exploring the continuing impact of Kuhn on the philosophy of science.

Connue pour ses travaux sur le goût, la consommation et le genre des objets, Leora Auslander nous donne ici un bel exemple d’écriture historique relativement inconnue en France. Synthétique et comparatif, le livre de l’historienne américaine aborde les trois révolutions – anglaise, américaine et française – sous l’angle de leur culture matérielle. Il s’agit pour elle de montrer combien les révolutions politiques s’appuient sur les émotions et la culture du quotidien pour fabriquer le sentimen...

The twentieth century saw extended development in the philosophy of science to incorporate contemporary expansions of scientific theory and investigation. Richard Rorty was a prominent and rather controversial thinker who maintained that all progress, from social change to scientific inquiry, was achieved through the redescription of existing vocabularies. However, this theory fails to describe revolutionary scientific progress. Thomas Kuhn’s theories of paradigm change, as first described in his seminal work The Structure of Scientific Revolutions, better portray this process. I (...) attempt to show this by applying Kuhn’s and Rorty’s views to examples of scientific progress and comparing the results. (shrink)

In 1845, John Henry Cardinal Newman wrote a treatise describing the development of Christian doctrine. Since then, his ideas have been challenged, in particular by Protestant theologians who have argued that the development of doctrine does not progress in either a smooth or linear path. In the philosophy of science, Thomas Kuhn's The Structure of Scientific Revolutions has challenged the idea that science is purely driven by objective and rational motives. In this paper, Kuhn's ideas are applied to the (...) development of Christian doctrine. Drawing from historical examples, it is shown that Kuhn's contextual approach to describe the progress of science aids in understanding the way doctrines themselves develop. Although this is not the first time that theology and Kuhn have conversed, the notion of doctrinal development being systematically and methodically shown to have parallels with Kuhn's ideas is novel. Ultimately, this work is another important step in building interdisciplinary links between science and theology. (shrink)

This book presents an analysis of global legal history in Modern times, questioning the effect of political revolutions since the 17th century on the legal field. Readers will discover a non-linear approach to legal history as this work investigates the ways in which law is created. These chapters look at factors in legal revolution such as the role of agents, the policy of applying and publicising legal norms, codification and the orientations of legal writing, and there is a focus (...) on the publicization of law. The author uses Herbert Hart's schemes to conceive law as a human artefact or convention, being the union between primary rules of obligations and secondary rules conferring powers. Here we learn about those secondary rules and the legal construction of the Modern state, and we question the extent to which codification and law reporting were likely to revolutionize the legal field. These chapters examine the hypothesis of a legal revolution that could have concerned many countries in modern times. To begin with, the book considers the legal aspect of the construction of Modern States in the 17th and 18th centuries. It goes on to examine the consequences of the codification movement as a legal revolution before looking at the so-called "constitutional" revolution, linked with the extension of judicial review in many countries after World War II. Finally, the book enquires into the construction of an EU legal order and international law. In each of these chapters, the author measures the scope of the change, how the secondary rules are concerned, the role of the professional lawyers and what are the characters of the new configuration of the legal field. This book provokes new debates in legal philosophy about the rule of change and will be of particular interest to researchers in the fields of law, theories of law, legal history, philosophy of law and historians more broadly. (shrink)

This paper argues that changes in philosophical practice will be most revolutionary not in the exercise of creativity and innovation in the content and substance of philosophical arguments - although these are not only important but also, to some extent, necessary for the survival of philosophy - but rather, in changes made: 1) to the philosophical environment and its tools; 2) to the kinds of bodies developed and expressed in those environments and in the course of using those tools; or (...) 3) to the styles, manners and mechanics of philosophical thinking. The introduction of these changes is what we should expect from the exercise of the imagination. To expect anything less would be to place in danger the ethical and political significance of thoughtfulness, not only in the context of the practice of philosophy, but also more broadly for the ethical and political health of the global community. (shrink)

Julia Kristeva’s work on the concept of revolt is marked by a temporal analysis that takes revolt to be a movement of return into the past that makes possible change, rebirth, and an open future. Such temporal revolt is, according to Kristeva, intimate, in that it touches on unconscious psychic structures and operates on the level of thought and creativity. But Kristeva simultaneously inherits Freud’s notion that the unconscious is timeless. How, I ask, can revolt be defined as a temporal (...) movement of return while at the same time being rooted in timelessness? I examine both Freud’s and Kristeva’s discussions of the timelessness of the unconscious and suggest that it needs to be understood not as non-temporal or outside of time, but rather as a temporal structure that challenges traditional philosophical conceptions of time. As such, the timelessness of the unconscious is far from being yet another instantiation of metaphysical presence. Rather, I see it as offering a challenge to both metaphysical presence and linear time, and indeed as making possible the retrospective movement of return that revolt for Kristeva must be. (shrink)

This article criticizes the attempts by Bas van Fraassen and Michael Friedman to address the challenge to rationality posed by the Kuhnian analysis of scientific revolutions. In the paper, I argue that van Fraassen's solution, which invokes a Sartrean theory of emotions to account for radical change, does not amount to justifying rationally the advancement of science but, rather, despite his protestations to the contrary, is an explanation of how change is effected. Friedman's approach, which appeals to philosophical developments (...) at a meta-theoretical level, does not really address the problem of rationality as posed by Kuhn's work. Instead of showing how, despite revolutions, scientific development is, indeed, rational, he gives a transcendental account of rational scientific progress. (shrink)

I propose a new perspective on the study of scientific revolutions. This is a transformation from an object-only perspective to an ontological perspective that properly treats objects and processes as distinct kinds. I begin my analysis by identifying an object bias in the study of scientific revolutions, where it takes the form of representing scientific revolutions as changes in classification of physical objects. I further explore the origins of this object bias. Findings from developmental psychology indicate that (...) children cannot distinguish processes from objects until the age of 7, but they have already developed a core system of object knowledge as early as 4 months of age. The persistence of this core system is responsible for the object bias among mature adults, i.e., the tendency to apply knowledge of physical objects to temporal processes. In light of the distinction between physical objects and temporal processes, I redraw the picture of the Copernican revolution. Rather than seeing it as a taxonomic shift from a geocentric to a heliocentric cosmology, we should understand it as a transformation from a conceptual system that was built around an object concept to one that was built around a process concept. (shrink)

This article was first published in 1982 in Educational Analysis (4, 75–91) and republished in 1998 (Hirst, P. H., & White, P. (Eds.), Philosophy of education: Major themes in the analytic tradition, Vol. 1, Philosophy and education, Part 1, pp. 61–78. London: Routledge). I was then a lecturer in philosophy of education at Sheffield University teaching the subject to Master’s students on both full- and part-time programmes. My first degree was in philosophy, read under D. W. Hamlyn and David Cooper (...) and, given their interests, inevitably emphasized the philosophy of language, in particular the work of Wittgenstein in this field. When I subsequently turned my attention to the philosophy of education it seemed obvious to me that there were serious problems with Professor Peters’ approach to language, and I had particular difficulties with his approach to criteria, meaning theory and what seemed an odd interpretation of a transcendental argument. This article thus set out to show that the then dominant form of philosophy of education seemed not to take account of developments in the philosophy of language that preceded Professor Peters’ early work by at least a decade and which cast serious doubt on the enterprise as it was then understood. As the articles in the 1998 collection indicate, I was not alone in thinking there was something amiss, although at the time I seemed to be ploughing a somewhat lonely furrow. In revisiting this early article some 30 years after it was first published I have found to my surprise that there is little I would now change, although I have been forcibly reminded of the very lively discussions Professor Peters and I had over these issues. The fact that there is little I would now add to, or subtract from, my critique is in itself a telling comment on the enduring and influential legacy of the approach to the philosophy of education that Professor Peters championed so powerfully. (shrink)

This is a partly provocative essay edited as a humanitarian study in philosophy of science and social philosophy. The starting point is Isaac Asimov’s famous sci-fi novella “Profession” (1957) to be “back” extrapolated to today’s relation between Thomas Kuhn’s “normal science” and “scientific revolutions” (1962). The latter should be accomplished by Asimov’s main personage George Platen’s ilk (called “feeble minded” in the novella) versus the “burned minded” professionals able only to “normal science”. Francis Fukuyama’s “end of history” in post-Hegelian (...) manner is now interpreted to an analogically supposed “end of scientific history” without “scientific revolutions” any more. The relevant dystopia of the prolonged or even “eternal” period of normal science is justified to the contemporary institution of science due to mechanisms such as “peer-review”, “impact-factor rating”, the projects’ competition for funding, etc. Positive feedbacks forcing all scientists needing careers to be more and more orthodox are demonstrated therefore establishing for that dystopia to be the real state of contemporary science. Two counterfactual case studies based correspondingly on Feyerabend’s “Against method” (1975) if Galilei should make his discoveries today and Sokal’s hoax (1996) if he suggested a scientific masterpiece to be really rejected by journals are discussed. Still one case study considering the abundance of Kelvin’s “clouds” on the horizon of today’s physics (dark matter, dark energy, entanglement, quantum gravitation, phenomena refuting the Big Bang, etc.) serves to verify the aforementioned conjecture that science has already entered that dystopia of eternal normal science. The conception of “ontomathematics” implying “creation ex nihilo” being scandalous for the dominating paradigm is sketched as an eventual revolutionary way out. An imaginary and utopic “happy end” reinterpreting the analogical “happy end” of Asimov’s “Profession” finishes the essay “instead of conclusion” relying on the Internet and AI in an increasingly “fluid” and anti-hierarchical society. (shrink)

'This is a very good and important book that is must reading for anyone interested in evolutionary economics and/or the relationship between history and economics. In addition, you get a very well documented and argued interpretation of long run capitalist development from the industrial revolution to the present that will be a standard reference... a first rate contribution to the discussion of how evolutionary economics should develop.' -Journal of Evolutionary Economics 'The book offers numerous insights into particular aspects of technological (...) change... Social theorists and policy advisors today need to be able to understand technological change in relation to cultural, political and economic life, and to situate contemporary developments in a longer term perspective. The authors provide a framework to do exactly that. Their book is a welcome demonstration of the usefulness of historical context for contemporary debates regarding science and technology policy.' -Business History 'A thought-provoking work that is valuable for more than its detailed account of the technological revolutions that shape our economy today. By directing our attention to a perspective outside the current wave, it shapes our thinking about events inside the current wave.' -Academy of Management Review 'This major contribution to economic history is the most impressive and convincing attempt I know to apply the concept of the 'long waves', a basic rhythm of historical development in the era of capitalism, to the entire stretch from eighteenth-century Lancashire to twenty-first-century Silicon Valley. It is also a call for economic history to escape from the handcuffs of narrow retrospective econometrics to the freedom of its vocation: understanding and explaining secular historical transformations.' -Eric Hobsbawm FBA, American Academy of Arts andamp; Sciences, Emeritus Professor of Social and Economic History, Birkbeck College; Author of The Age of Extremes: The Short Twentieth Century 1914-1991The Internet and mobile telephones have made everyone more aware than ever of the computer revolution and its effects on the economy and society. 'As Time Goes By' puts this revolution in the perspective of previous waves of technical change: steam-powered mechanization, electrification, and motorization. It argues for a theory of reasoned economic history which assigns a central place to these successive technological revolutions. (shrink)

Thomas Kuhn's Structure of Scientific Revolutions became the most widely read book about science in the twentieth century. His terms 'paradigm' and 'scientific revolution' entered everyday speech, but they remain controversial. In the second half of the twentieth century, the new field of cognitive science combined empirical psychology, computer science, and neuroscience. In this book, the theories of concepts developed by cognitive scientists are used to evaluate and extend Kuhn's most influential ideas. Based on case studies of the Copernican (...) revolution, the discovery of nuclear fission, and an elaboration of Kuhn's famous 'ducks and geese' example of concept learning, this volume, first published in 2006, offers accounts of the nature of normal and revolutionary science, the function of anomalies, and the nature of incommensurability. (shrink)

The Internet and mobile telephones have made everyone more aware than ever of the computer revolution and its effects on the economy and society. As Time Goes By puts this revolution in the perspective of previous waves of technical change: steam-powered mechanization, electrification, and motorization. It argues for a theory of reasoned economic history which assigns a central place to these successive technological revolutions.

(2005). Wonder in the face of scientific revolutions: Adam Smith on Newton's ‘Proof’ of Copernicanism. British Journal for the History of Philosophy: Vol. 13, No. 4, pp. 697-732. doi: 10.1080/09608780500293042.

In a previous article we have shown that Kuhn's theory of concepts is independently supported by recent research in cognitive psychology. In this paper we propose a cognitive re-reading of Kuhn's cyclical model of scientific revolutions: all of the important features of the model may now be seen as consequences of a more fundamental account of the nature of concepts and their dynamics. We begin by examining incommensurability, the central theme of Kuhn's theory of scientific revolutions, according to (...) two different cognitive models of concept representation. We provide new support for Kuhn 's mature views that incommensurability can be caused by changes in only a few concepts, that even incommensurable conceptual systems can be rationally compared, and that scientific change of the most radical sort—the type labeled revolutionary in earlier studies—does not have to occur holistically and abruptly, but can be achieved by a historically more plausible accumulation of smaller changes. We go on to suggest that the parallel accounts of concepts found in Kuhn and in cognitive science lead to a new understanding of the nature of normal science, of the transition from normal science to crisis, and of scientific revolutions. The same account enables us to understand how scientific communities split to create groups supporting new paradigms, and to resolve various outstanding problems. In particular, we can identify the kind of change needed to create a revolution rather precisely. This new analysis also suggests reasons for the unidirectionality of scientific change. (shrink)