A study in the logic of theory change, examining the properties of maxichoice contraction and revision operations.

The book presents the results of the joint annual conference of the four Operations Research Societies DGOR, GM\OR, \GOR and SVOR, held in Vienna in 1990.

This paper is concerned with formal aspects of the logic of theory change, and in particular with the process of shrinking or contracting a theory to eliminate a proposition. It continues work in the area by the authors and Peter Gärdenfors. The paper defines a notion of safe contraction of a set of propositions, shows that it satisfies the Gärdenfors postulates for contraction and thus can be represented as a partial meet contraction, and studies its properties (...) both in general and under various natural constraints. (shrink)

Examines the link between nonmonotonic inference relations and theory revision operations, focusing on the correspondence between abstract properties which each may satisfy.

Describes and discusses the rather special behaviour of one of the postulates in the AGM account of theory change.

This thesis consists in six articles and a comprehensive summary. • The pourpose of the summary is to introduce the AGM theory of belief change and to exemplify the diversity and significance of the research that has been inspired by the AGM article in the last 25 years. The research areas associated with AGM was divided in three parts: criticisms, where we discussed some of the more common criticisms of AGM. Extensions where the most common extensions and variations (...) of AGM are presented and applications where we provided an overview of applications and connections with other areas of research. • Article I elaborates on the connection between partial meet contractions [AGM85] and kernel contractions [Han94a] in belief change theory. Also both functions are equivalent in belief sets, there are notequivalent in belief bases. A way to define incision functions from selection functions and vice versa is presented. It is explained under which conditions there are exact correspondences between selection and incision functions so that the same contraction operations can be obtained by using either of them. • Article II proposes an axiomatic characterization for ensconcement-based contraction functions, belief base functions proposed byWilliams and relates this function with other kinds of base contraction functions. • Article III adapts the Fermé and Hansson model of Shielded Contraction [FH01] as well as Hansson et all Credibility-Limited Revision [HFCF01] for belief bases, to join two of the many variations of the AGM model [AGM85], i.e. those in which knowledge is represented through belief bases instead of logic theories, and those in which the object of the epistemic change does not get the priority over the existing information as it is the case in the AGM model. • Article IV introduces revision by comparison a refined method for changing beliefs by specifying constraints on the relative plausibility of propositions. Like the earlier belief revision models, the method proposed is a qualitative one, in the sense that no numbers are needed in order to specify the posterior plausibility of the new information. The method uses reference beliefs in order to determine the degree of entrenchment of the newly accepted piece of information. Two kinds of semantics for this idea are proposed and a logical characterization of the new model is given. • Article V focuses on the extension of AGM that allows change for a belief base by a set of sentences instead of a single sentence. In [FH94], Fuhrmann and Hansson presented an axiomatic for Multiple Contraction and a construction based on the AGM Partial Meet Contraction. This essay proposes for their model another way to construct functions: Multiple Kernel Contraction, that is a modification of Kernel Contraction,proposed by Hansson [Han94a] to construct classical AGM contractions and belief base contractions. • Article VI relates AGM model with the DFT model proposed by Carlos Alchourrón [Alc93]. Alchourrón devoted his last years to the analysis of the notion of defeasible conditionalization. His definition of the defeasible conditional is given in terms of strict implication operator and a modal operator f which is interpreted as a revision function at the language level. This essay points out that this underlying revision function is more general than AGM revision. In addition, a complete characterization of that more general kind of revision that permits to unify models of revision given by other authors is given. (shrink)

The postulate of Recovery, among the six postulates for theory contraction, formulated and studied by Alchourrón, Gärdenfors and Makinson is the one that has provoked most controversy. In this article we construct withdrawal functions that do not satisfy Recovery, but try to preserve minimal change, and relate these withdrawal functions with the AGM contraction functions.

The paper surveys some recent work on formal aspects of the logic of theory change. It begins with a general discussion of the intuitive processes of contraction and revision of a theory, and of differing strategies for their formal study. Specific work is then described, notably Gärdenfors'' postulates for contraction and revision, maxichoice contraction and revision functions and the condition of orderliness, partial meet contraction and revision functions and the condition of relationality, and finally the operations (...) of safe contraction and revision. Verifications and proofs are omitted, with references given to the literature, but definitions and principal results are presented with rigour, along with discussion of their significance. (shrink)

Belief revision theory and philosophy of science both aspire to shed light on the dynamics of knowledge – on how our view of the world changes in the light of new evidence. Yet these two areas of research have long seemed strangely detached from each other, as witnessed by the small number of cross-references and researchers working in both domains. One may speculate as to what has brought about this surprising, and perhaps unfortunate, state of affairs. One factor may (...) be that while belief revision theory has traditionally been pursued in a bottom- up manner, focusing on the endeavors of single inquirers, philosophers of science, inspired by logical empiricism, have tended to be more interested in science as a multi-agent or agent-independent phenomenon. (shrink)

An investigation of what might be called the logical formalization of the process of theory change due to anomalies is presented. By anomaly, we mean an observed fact falling into the explanatory scope of a theory that does not agree with the theory prevision. A classical approach to restore the explicative power of a theory faced with an anomaly is to propose new, tentative auxiliary hypotheses which, along with part of the old set of auxiliary (...) hypotheses, are able to solve the anomaly. After laying down some conclusions about the structure of such process, we propose a multi-modal and non-monotonic logical framework able to represent some key aspects of this important facet of the dynamics of scientific theories. Due to the necessity of accommodating incompatible tentative hypotheses, this framework incorporates a weak form of paraconsistency. As a case study, we analyze the anomalous behaviour of the planet Uranus that threatened the Newtonian celestial mechanics for more than half a century and gave rise to the discovery of Neptune. (shrink)

The logic of change formulated by K. Świętorzecka, has its motivation coming from the Aristotelian theory of substantial change which is undrstood as a transformation consisting in the disappearing and becoming of individual substances. The transition: becoming/disapearing (and conversely) is expressed in by the primitive operator C, to be read: it changes that …, and it is mapped by the progressively expanding language. We are interested in attributive changes of individual substances. We consider a formalism with (...) two non-normal and not mutually definable operators of possible and necessary change, inspired by Aristotelian distinction of accidental and essential attributes. From we adopt the idea that temporal concepts are defined via change operators, and the idea of an expanding language. In what follows, We axiomatise our new logic and describe its semantics, giving the proof of its completeness. We compare our formalism with selected modal logics. (shrink)

Ever since [4], systems of spheres have been considered to give an intuitive and elegant way to give a semantics for logics of theory- or belief- change. Several authors [5, 11] have considered giving up the rather strong assumption that systems of spheres be linearly ordered by inclusion. These more general structures are called hypertheories after [8]. It is shown that none of the proposed logics induced by these weaker structures are compact and thus cannot be given a (...) strongly complete axiomatization in a finitary logic. Complete infinitary axiomatizations are given for several intuitive logics based on hypertheories that are not linearly ordered by inclusion. (shrink)

The book focuses on the modern understanding of human life-forms as constructs that followed an evolutionary history. The author thus finds science confronted with two questions: firstly, how the transgression of the virtual threshold between natural and cultural history was possible, secondly, how the socio-cultural constructs were able to develop in the course of history the way they did. The discussion concentrates on the problem of determining a processual logic in the development of societal structures as well as in (...) the development of cognition. The focus of attention is the historico-genetic reconstruction of cognition. The book was originally published in German as Historisch-genetische Theorie der Kultur (Weilerswist 2000: Velbrück). (shrink)

I explore how the nature, scope, and limits of the knowledge obtained in orbital dynamics has changed in recent years. Innovations in the design of spacecraft trajectories, as well as in astronomy, have led to new logics of theory-testing—that is, new research methodologies—in orbital dynamics. These methodologies—which combine resonance overlap theories, numerical experiments, and the implementation of space missions—were developed in response to the discovery of chaotic dynamical systems in our solar system. In the past few decades, they have (...) replaced the methodology that dominated orbital research in the centuries following Newton's Principia. As a result, the kind of knowledge achieved by orbital research has changed: we can know how orbiting bodies in chaotic systems behave, but only over sufficiently short time scales; and we can reliably measure those temporal limitations, using Lyapunov time. (shrink)

Imre Lakatos' "methodology of scientific research programs" and Alasdair MacIntyre's "tradition-constituted enquiry" are two sustained attempts to overcome the assumptions of logical empiricism, while saving the appearance that theory-change is rational. The key difference between them is their antithetical stand on the issue of incommensurability between large-scale theories. This divergence generates other areas of disagreement; the most important are the relevance of the historical record and the presence of decision criteria that are common to rival programs. I show (...) that Lakatos' rejection of the incommensurability thesis and dismissal of actual history are motivated by the belief that neither are compatible with the rationality of theory-change. If MacIntyre can deny the necessity of dispensing with the historical record, and show that incommensurability and the consequent absence of shared decision criteria are compatible with rationality in theory-change, then Lakatos' argument will lose its force, and MacIntyre will better honor the intention to take seriously the historicality of science. I argue that MacIntyre can dissolve tensions between incommensurability and rationality in theory-change if he is able, first, to distinguish a sense of the incommensurability thesis that preserves genuine rivalry between theories, and second, to show that the possibility of rationality in theory-change depends not on the presence of common decision criteria, but on the fact that traditions can fail by their own standards. After reconstructing and examining the argument, I conclude that the notion of a tradition's "internal failure" is coherent, but that it leaves crucial questions about the epistemology and ontology of traditions that must be answered if MacIntyre's proposal is to constitute a genuine improvement on Lakatos. (shrink)

ANGLO-AMERICAN PHILOSOPHY OF SCIENCE has tended to define itself squarely against the kinds of so-called metaphysical approaches that have characterized so-called continental philosophy in the line of descent from Husserl. Indeed, Husserl’s project of phenomenological enquiry was the target of criticism by Frege—and later by Gilbert Ryle—which pretty much set the agenda for subsequent debate. That project seemed to them some form of argument that reveals his basically psychologistic approach, one that purported to address issues of truth, validity, rational warrant, (...) and so forth, but which fell far short of the logical rigor attained by thinkers in the analytic tradition. Thus Husserl might claim—like Descartes and Kant before him—to be raising questions about the a priori forms of human knowledge and experience, forms that were given or necessarily presupposed in every possible act of cognition. Moreover, he might claim to have advanced beyond Kant in distinguishing more clearly between formal and transcendental logic, or judgments whose necessity follows from the ground rules of this or that logically binding system of thought, and judgments that result from a rigorous reflection on the genesis and structure of human understanding in general. However these claims counted for little with Husserl’s critics in the other, that is, post-Fregean analytical camp. What they chiefly objected to in Husserl’s project was the approach via thoughts and ideas in the mind of some perceiving or reasoning subject, even though Husserl was very often at pains to reject any merely empirical or psychologistic construal of his claims. To their way of thinking, all this talk about transcendental truth- and validity-conditions was just another variant of the bad old Cartesian-Kantian retreat to consciousness as the last court of appeal in epistemological matters. Only by rejecting that entire line of thought—that is to say, by adopting a strictly analytical or logico-semantic approach—could philosophy at last break free of its attachment to naive, subject-centered, or metaphysical notions of meaning and truth. (shrink)

The classical qualitative theory of belief change due to Alchourrón, Gärdenfors and Makinson has been widely known as being characterised by two packages of postulates. While the basic package consists of six postulates and is very weak, the full package that adds two further postulates is very strong. I revisit two classic constructions of theory contraction, viz., relational possible worlds contraction and entrenchment-based contraction and argue that four intermediate levels can be distinguished that play - or ought (...) to play - important roles within qualitative belief revision theory. Levels 3 and 4 encode two ways of interpreting the idea of imperfect discrimination of the plausibilities of possible worlds or propositions. (shrink)

A number of seminal papers on the logic of belief change by Alchourrön, Gärden-fors, and Makinson have given rise to what is now known as the AGM paradigm. The present discussion note is a response to Neil Tennant's [1994], which aims at a critical appraisal of the AGM approach and the introduction of an alternative approach. We show that important parts of Tennants's critical remarks are based on misunderstandings or on lack of information. In the course of doing (...) this, we attend to some central philosophical issues in the theory of belief change, such as the choice of a representation for belief states and the meaning of an idealized rational agent. (shrink)

To sentential language we add an operator C to be read as ‘it changes that…’ and present an axiomatic system in the frame of classical logic to catch some meaning of the term ‘change’. A typical axiom is e.g.: CA implies, a basic rule is: from A it may be inferred (theorems do not change). So this system is not regular. On the semantic level we introduce stages (of the development of some world, of some agents’ convictions (...) or of some argumentation) at which a sentence may be true or false. It turns out that with the help of C, an operator N can be defined whose intuitive meaning is ‘on the next occasion…’ and which behaves like A.N. Prior’s F (and also like the T operator of G.H. von Wright’s read ‘… and next…’). In a book by Świetorzecka (2008) cited below, the philosophical background is described which is the Aristotelian theory of substantial change. The author of this book shows also some metalogical properties of this logic. The aim of this text now is to present a formal extraction of Świetorzecka (2008) with a shortened axiomatisation and to describe some metalogical results. (shrink)

I argue that the lived experience we, the human species, are going through in 2020 is no longer an epoch of changes but a change of epoch. Post-pandemic (and any other areas of experience you could post-) is becoming meaningless in a change of epoch. My argument is based on the history of the colonial matrix of power rather than in particular thematic histories which, in this case, will be the history of pandemics and the history of the (...) economy. Both are working together, globally now, and entangled in the colonial matrix of power, which can not be found in the origin of the universe, in Babylon or in Greece. It did not exist until the 16th century in the Atlantic, the Black and the White, the North and the South. The logic of coloniality is the logic of the invisible and it is by understanding its historical foundation, its unfolding and the radical transformations in the past two decades, that the signs of the change of epoch can be perceived and understood. (shrink)

The aim of this paper is to elucidate the question of whether Newtonian mechanics can be derived from relativity theory. Physicists agree that classical mechanics constitutes a limiting case of relativity theory. By contrast, philosophers of science like Kuhn and Feyerabend affirm that classical mechanics cannot be deduced from relativity theory because of the incommensurability between both theories; thus what we obtain when we take the limit c in relativistic mechanics cannot be Newtonian mechanics sensu stricto. In (...) this paper I focus on the alleged change of reference of the term mass in the transition from one theory to the other. Contradicting Kuhn and Feyerabend, special relativity theory supports the view that the mass of an object is a characteristic property of the object, that it has the same value in whatever frame of reference it is measured, and that it does not depend on whether the object is in motion or at rest. Thus mass preserves the reference through the change of theory, and the existence of a Newtonian limit of relativity theory provides a good example of the rationality of theory change in mathematical physics. (shrink)

The problems that surround iterated contractions and expansions of beliefs are approached by studying hypertheories, a generalisation of Adam Grove's notion of systems of spheres. By using a language with dynamic and doxastic operators different ideas about the basic nature of belief change are axiomatised. It is shown that by imposing quite natural constraints on how hypertheories may change, the basic logics for belief change can be strengthened considerably to bring one closer to a theory of (...) iterated belief change. It is then argued that the logic of expansion, in particular, cannot without loss of generality be strengthened any further to allow for a full logic of iterated belief change. To remedy this situation a notion of directed expansion is introduced that allows for a full logic of iterated belief change. The new operation is given an axiomatisation that is complete for linear hypertheories. (shrink)

‘During the 1930’s and early 1940’s a thoughtful observer might well have tended towards the conclusion that logic would break off from the ancient moorings that kept it joined to philosophy, and either link itself to mathematics, or go its own way as an independent discipline’. Professor Rescher finds however, on the contrary, that the literature of the last ten to fifteen years displays a significant cluster of developments in logic that may be called philosophical. Branches of logical (...) theory have been developed with philosophical applications in mind. Foundations have been laid for an exact logic of obligation, preference, choice, command; the traditional problem of universals has been focused from the perspective of mathematical logic; existence, time, tense, change and process is being explored with techniques of logic; literature on the logic of belief, hypothesis and probability is extensive. (shrink)

Belief Revision is a well-established field of research that deals with how agents rationally change their minds in the face of new information. The milestone of Belief Revision is a general and versatile formal framework introduced by Alchourrón, Gärdenfors and Makinson, known as the AGM paradigm, which has been, to this date, the dominant model within the field. A main shortcoming of the AGM paradigm, as originally proposed, is its lack of any guidelines for relevant change. To remedy (...) this weakness, Parikh proposed a relevance-sensitive axiom, which applies on splittable theories; i.e., theories that can be divided into syntax-disjoint compartments. The aim of this article is to provide an epistemological interpretation of the dynamics of splittable theories, from the perspective of Kuhn's inuential work on the evolution of scientific knowledge, through the consideration of principal belief-change scenarios. The whole study establishes a conceptual bridge between rational belief revision and traditional philosophy of science, which sheds light on the application of formal epistemological tools on the dynamics of knowledge. (shrink)

Philosophers of science discuss whether theory selection depends on aesthetic judgments or criteria, and whether these putatively aesthetic features are genuinely extra-epistemic. As examples, judgments involving criteria such as simplicity and symmetry are often cited. However, other theory selection criteria, such as fecundity, coherence, internal consistency, and fertility, more closely match those criteria used in art contexts and by scholars working in aesthetics. Paying closer attention to the way these criteria are used in art contexts allows us to (...) understand some evaluative and developmental practices in scientific theory selection as genuinely aesthetic, enlarging the scope of the goals of science. (shrink)

The intention of the presented paper is to establish within a certain modal semantic based on the situational ontology a description of the phenomenon of substantial change, which originally had been formulated within Aristotelian metaphysics – a theory based in reistic ontology. We understand substantial changesto be such changes whose subjects are primary substances (πρωται ουσι αι ) conceived as actually existing individual essences. The analysed changeability is of an existential character - it pertains to the existence of (...) those substances. The formalised description of the chosen changes, constructed in part (1) of the study, takes into consideration the necessary condition for their occurrence: the disappearing and coming into being of successively becoming substances. Part (2) presents the manner in which it is possible to reformulate the obtained characteristic of substantial change in order to create a description of a particular variety of situational changes, which belong, in turn, to the intended interpretation of modal sentential logic of change LCG - a calculus in which change is a primitive concept precised with the help of two one-argument operators C and G, read respectively as: it changes that…, a change is enabled by this, that ….. (shrink)

Various representation results have been established for logics of belief revision, in terms of remainder sets, epistemic entrenchment, systems of spheres and so on. In this paper I present another representation for logics of belief revision, as an algebra of theories. I show that an algebra of theories, enriched with a set of rejection operations, provides a suitable algebraic framework to characterize the theory change operations of systems of belief revision. The theory change operations arise as (...) power operations of the conjunction and disjunction connectives of the underlying logic. (shrink)

This work contrasts conservative or minimally mutilating revisions of empirical theories as they are identified in the presently dominant AGM model of formal belief revision and the structuralist program for the reconstruction of empirical theories. The aim is to make understandable why both approaches only partly succeed in substantially informing and formally restraining the issue. With respect to the rationality of minimal change, the overall result is negative. Readers with an interest in formal epistemology are provided with application cases (...) (mercury anomaly, revision of early thermo-dynamics, introduction of the neutrino), the historically inclined reader is offered a systematic perspective. The discussion can largely be followed without a background in formal logic. (shrink)

Synchronic norms of theory choice, a traditional concern in scientific methodology, restrict the theories one can choose in light of given information. Diachronic norms of theory change, as studied in belief revision, restrict how one should change one’s current beliefs in light of new information. Learning norms concern how best to arrive at true beliefs. In this paper, we undertake to forge some rigorous logical relations between the three topics. Concerning, we explicate inductive truth conduciveness in (...) terms of optimally direct convergence to the truth, where optimal directness is explicated in terms of reversals and cycles of opinion prior to convergence. Concerning, we explicate Ockham’s razor and related principles of choice in terms of the information topology of the empirical problem context and show that the principles are necessary for reversal or cycle optimal convergence to the truth. Concerning, we weaken the standard principles of agm belief revision theory in intuitive ways that are also necessary for reversal or cycle optimal convergence. Then we show that some of our weakened principles of change entail corresponding principles of choice, completing the triangle of relations between,, and. (shrink)

In this paper it is shown how the DRT (Discourse Representation Theory) treatment of temporal anaphora can be formalized within a version of Montague Semantics that is based on classical type logic.

When first published twenty years ago, The Logic of Medicine presented a new way of thinking about clinical medicine as a scholarly discipline as well as a profession. Since then, advances in research and technology have revolutionized both the practice and theory of medicine. In this new, extensively rewritten edition, Dr. Murphy includes changes to show how these different areas of scholarship may affect details of "the logic of medicine" without compromising its fundamental coherence. New to this (...) edition are discussions of the challenge of the flood of new empirical data, new ideas in genetics, molecular biology, homeostasis, pathogenesis, cancer, aging, and Alzheimer's disease. Murphy also comments on such new theoretical topics as dynamic systems, chaos, and fractals and their impact on the burgeoning fields of philosophy and practice of medicine. Written with medical students in mind, the book includes a glossary, many new examples, and problems for solutions with comments on each. An entirely new chapter deals with modeling. Clinicians and researchers will also find the principles thought-provoking and illuminating. (shrink)

Two views of scientific theories dominated the philosophy of science during the twentieth century, the syntactic view of the logical empiricists and the semantic view of their successors. I show that neither view is adequate to provide a proper understanding of the connections that exist between theories at different times. I outline a new approach, a hybrid of the two, that provides the right structural connection between earlier and later theories, and that takes due account of the importance of the (...) mathematical models of a theory and of the various distinct formulations that pick out these models. (shrink)

This essay is a logico?philosophical critique of the Marxian system of sociology with special reference to the theory of social change. To every change in the natural order (taken in conjunction with the technological order) corresponds an appropriate change in the human order, that is, in the system of social relations. This, it is shown, is the fundamental Marxian thesis regarding social equilibrium. And accordingly the key idea regarding social change is that a gradually maturing (...) inherent disproportion between the two orders is the basic condition of social change, eventually leading to the establishment of a new social equilibrium at a higher level. A close examination of the concept of mode of production and changes therein is attempted in the course of elucidating the above thesis. It is argued that the technological interpretation of the concept of mode of production conflicts with the Marxian anthropology and that we should have a structural interpretation according to which it will refer to the economy as a whole and will include among other elements production relations. This interpretation leads the discussion into one of the central problems of Marxism, namely, the relation between the mode of production and the social system. It is argued that the social system is basic to Marx and after a close analysis of the concept of system it is shown that the Marxian theory of base and superstructure rests mainly on confusion of conceptual orientations. This, it is shown, is connected with a fundamental idea of Marxism, viz., that of a system without a transcendent centre. This essay endeavours to prove that such an idea is logically untenable. Hence the Marxian Laws of Transformation of Quantity into Quality and Negation of Negation are examined and shown logically untenable. The last section discusses the question about the determinant of technological change and eventually of social change. Three possible Marxian solutions are examined: (a) in terms of needs ? it is argued that this is inconsistent with Marx's theory of man and labour; (b) in terms of science and new ideas ? it is shown that this ultimately goes contrary to Marxian materialism and positivism; and finally, (c) the systemic solution in terms of the dialectic of nature and man is subjected to logical scrutiny and it is shown that this cannot be consistent and valid without involving a trans?historical standpoint; for, it is argued, the idea of the self?directing Humanity on which it rests is a self?contradictory notion. (shrink)

In this article, it was first presented Moore’s paradox per se and after the author focused on the logical perspective — at first he analyzed these considerations in the field of so-called standard epistemic logic and after on the formal theory of belief change.

This paper shows how the dynamic interpretation of natural language introduced in work by Hans Kamp and Irene Heim can be modeled in classical type logic. This provides a synthesis between Richard Montague's theory of natural language semantics and the work by Kamp and Heim.

I consider the idea of a propositional logic of location based on the following semantic framework, derived from ideas of Prior. We have a collection L of locations and a collection S of statements such that a statement may be evaluated for truth at each location. Typically one and the same statement may be true at one location and false at another. Given this semantic framework we may proceed in two ways: introducing names for locations, predicates for the relations (...) among them and an “at” preposition to express the value of statements at locations; or introduce statement operators which do not name locations but whose truth-conditional effect depends on the truth or falsity of embedded statements at various locations. The latter is akin to Prior’s approach to tense logic. In any logic of location there will be some basic operators which we can define. By ringing the changes on the topology of locations, different logical systems may be generated, and the challenge for the logician is then in each case to find operators, axioms and rules yielding a proof theory adequate to the semantics. The generality of the approach is illustrated with familiar and not so familiar examples from modal, tense and place logic, mathematics, and even the logic of games. To the memory of Ted Dawson, who introduced me to philosophy and the writings of Arthur Prior. (shrink)

A longstanding criticism of Ernest Nagel's model of reduction is that it fails to take theory change into account. This criticism builds on the received view that Nagelian reductions are incompatible with theory change. This article challenges the received view by showing that Nagel's model can easily accommodate theory change. Indeed, Nagel's model is essentially static as it only gives unchanging formal and nonformal conditions for reduction; in contrast, theory change belongs to (...) the dynamic history of science; as a result, the application of Nagel's model to scientific knowledge from different historical periods yields a series of Nagelian reductions of different degrees of reductive success. This Nagelian treatment of theory change is illustrated by considering the enterprise of reducing thermodynamics to statistical mechanics in the late nineteenth century. It is also contended that, in handling theory change Nagel's model has greater merits than subsequent models (exemplified by Kenneth Schaffner's general reduction-replacement model). This article concludes by suggesting that Nagel's model of reduction deals with theory change exactly in the same way as logical empiricism does with historicism. (shrink)

Re-thinking the political workings of habit and habituation, this article suggests, is vital to understanding the logics and possibilities of social change today. Any endeavour to explore habit’s affirmative potential, however, must confront its legacies as a colonialist, imperialist and capitalist technology. As a means to explore what it is that differentiates contemporary neoliberal modes of governing through habit from more critical approaches, this article compares contemporary ‘nudge’ theory and policy, as espoused by the behavioural economist Richard Thaler (...) and the legal scholar Cass Sunstein, with the pragmatist philosophies of habit offered by John Dewey, William James and Shannon Sullivan. While nudge advocates focus on how policy-makers and corporate leaders can intervene in the ‘choice architectures’ that surround us to outsmart or bypass problematic human tendencies, I argue, pragmatist philosophers appreciate the necessity of collective efforts to develop new and flexible forms of habituation in order to engender more enduring and democratic forms of social transformation. (shrink)

Traditional theories construe approximate truth or truthlikeness as a measure of closeness to facts, singular facts, and idealization as an act of either assuming zero of otherwise very small differences from facts or imagining ideal conditions under which scientific laws are either approximately true or will be so when the conditions are relaxed. I first explain the serious but not insurmountable difficulties for the theories of approximation, and then argue that more serious and perhaps insurmountable difficulties for the theory (...) of idealization force us to sever its close tie to approximation. This leads to an appreciation of lawlikeness as a measure of closeness to laws, which I argue is the real measure of idealization whose main purpose is to carve nature at its joints. (shrink)

This is the first book that integrates nonmonotonic reasoning and belief change into a single framework from an artificial intelligence logic point-of-view.

This work explores the conceptual and empirical issues of the concept of knowledge and its relation to the pattern of our belief change, from formal and experimental perspectives. Part I gives an analysis of knowledge (called Sustainability) that is formally represented and naturalistically plausible at the same time, which is claimed to be a synthesized view of knowledge, covering not only empirical knowledge, but also knowledge of future, practical knowledge, mathematical knowledge, knowledge of general facts. Part II tries to (...) formalize the natural pattern of belief change assumed in Sustainability in terms of a specific formal theory of belief change, after carefully examining the notions of belief, belief change, and Information, from which the cognitive function F in Chapter 3 is actually constructed, which is later implemented by a computer program and its behavior against random input is demonstrated. In Part III we proceed to examine the analysis empirically. In particular, we will investigate Sustainability from the developmental point of view. We first justify experimental approach in philosophy as a legitimate method of philosophical investigation, and then developmental approach in particular. The specific proposal of experiment here is what we call the Gettier Task, an analogue of the famous false-belief task in developmental psychology, which has been much discussed in philosophy of mind. Two versions of the Gettier Task were tested on children aged from 6 to 12, and we claim that the data obtained empirically supports our analysis of knowledge, or Sustainability. (shrink)

Hsun K'uang was one of the thinkers of the Warring States period, and he occupies an important place in the history of Chinese thought. He was also an outstanding Chinese logician. He broadened the realm of logical theory and applied logic to the ideological struggle in his time. This article will be devoted to a review of the outline and characteristics of the logical thought advanced in his famous article "Cheng-ming p'ien" [Correct Nomenclature].

Practitioners of science treat evidence as a separate and objective body of materials that is independent of, and possibly also prior to, all of theorizing. Philosophers of science, by contrast, are increasingly wary of the role of theory in testing and measurement contexts, and hence have problematized the notion of evidence as prior or independent, even in the context of measurement. This paper argues that there is an important sense in which empirical certification of a quantity, via measurement, is (...) indeed prior to theorizing, albeit not necessarily in order of time. The case for this priority distinguishes between the certification of the measurability of a given quantity, as a quantity appropriately measured on a specified scale, and the epistemic warrant due to an assignment of a specific magnitude to that quantity on a given occasion. The result is an account of the certification of a measurable quantity, independent of any theory in which that quantity features. The effect is to render certification of quantities theory-neutral. The aim of the essay is thus to bolster and re-establish a more nuanced empiricist view, via building a case for quantity certification as the epistemic basis (i.e., foundation) of the scientific enterprise. (shrink)

Customary discussions of quantum measurements are unrealistic, in the sense that they do not reflect what happens in most actual measurements even under ideal circumstances. Even theories of measurement which discard the projection postulate tend to retain two unrealistic assumptions of the von Neumann theory: that a measurement consists of a single physical interaction, and that the topic of every measurement is information wholly contained in the quantum state of the object of measurement. I suggest that these unrealistic assumptions (...) originate from an overly literal interpretation of the operator formalism of quantum mechanics. I also suggest, following Park, that some issues can be clarified by distinguishing the sense of the term ''''measurement'''' occurring in the quantum-mechanical operator formalism, and the sense of ''''measurement'''' that refers to actual processes of gaining information about the physical world. (shrink)