The philosophical debate about quantum logic between the late 1960s and the early 1980s was generated mainly by Putnam's claims that quantum mechanics empirically motivates introducing a new form of logic, that such an empirically founded quantum logic is the `true' logic, and that adopting quantum logic would resolve all the paradoxes of quantum mechanics. Most of that debate focussed on the latter claim, reaching the conclusion that it was mistaken. This chapter will attempt to clarify the possible misunderstandings surrounding (...) the more radical claims about the revision of logic, assessing them in particular both in the context of more general quantum-like theories (in the framework of von Neumann algebras), and against the background of the current state of play in the philosophy and interpretation of quantum mechanics. Characteristically, the conclusions that might be drawn depend crucially on which of the currently proposed solutions to the measurement problem is adopted. (shrink)

The last decade has seen significant developments in UK health policy, with are largely claimed to be evidence based. However, such a characterisation ought, in many cases, to be questioned. Policies can be broadly understood as based primarily on either a logical or empirical case. In the absence of relevant empirical evidence, policymakers understandably appeal to logical cases. Once such evidence is available, however, it can inform policy and enable the logical case to be set aside. Such (...) a linear policy process is not always the reality, and logical cases often continue to guide policy decisions in direct opposition to empirical evidence. In this paper, I discuss two recent examples of this disconnect between logical and empirical cases in UK health policy. The first—organ donation—illustrates an example of a significant policy change being made in opposition to the evidence. I refer to this as the improvidence approach. The second—abortion—provides an example of policymakers not making a change that has extensive supporting data. I refer to this using the more recognisable language of the precautionary approach. Ultimately, I argue that both the improvidence and precautionary approaches are examples of problematic public policy where policymakers provide no explicit justification for going against the evidence. (shrink)

I argue, in opposition, to the traditional approach that systematic psychological inquiry of a type frequently practiced by people like Edwards, Kahneman and Tversky, and Schum is relevant to the choice of the best inductive logic. In the paper, I present some provisional arguments against the traditional view and sketch some of the relevant evidence. This effort is made with the aim of aiding the development of a naturalistic epistemology.

Theory of Mind (ToM), the cognitive capacity to attribute internal mental states to oneself and others, is a crucial component of social skills. Its formal study has become important, witness recent research on reasoning and information update by intelligent agents, and some proposals for its formal modelling have put forward settings based on Epistemic Logic (EL). Still, due to intrinsic idealisations, it is questionable whether EL can be used to model the high-order cognition of ‘real’ agents. This manuscript proposes a (...) framework that takes visibility, memory, perspective and communication as the main factors underpinning mental attributions. This is more in-line with findings in cognitive science and allows us to model well-known False-Belief Tasks that are typically used in testing people's ToM. We discuss some of the framework's technical features, arguing why it does justice to empirical observations. (shrink)

Logic and philosophy of science share a long history, though contacts have gone through ups and downs. This paper is a brief survey of some major themes in logical studies of empirical theories, including links to computer science and current studies of rational agency. The survey has no new results: we just try to make some things into common knowledge.

I distinguish a priori knowledge from a priori truths or statements. A priori knowledge either is evident or is derived from evident premisses by means of correct reasoning. An a priori statement is one that reflects features of the conceptual framework within which it is placed. The statement either describes semantic relations between concepts of the framework or it characterizes the application of the framework to experience and the world. An a priori statement is not necessarily part of anyone’s a (...) priori knowledge. I also distinguish empirical knowledge from empirical statements. Both statements and theories are empirical if they are designed to characterize features of experience and the world. Knowledge is empirical if it fits experience; thus, one must check to see whether it fits. We do not obtain knowledge of logical systems by rational insight of evident truths and careful deductions from evident truths. Adequate logical systems are developed by trial and error. Logical knowledge is empirical knowledge that is not generally a priori. It is empirical knowledge of a priori truths and principles of our conceptual systems. Logical systems are empirical theories of these truths and principles. (shrink)

The laws of classical logic are taken to be logical truths, which in turn are taken to hold objectively. However, we might question our faith in these truths: why are they true? One general approach, proposed by Putnam [8] and more recently Dickson [3] or Maddy [5], is to adopt empiricism about logic. On this view, logical truths are true because they are true of the world alone – this gives logical truths an air of objectivity. Putnam (...) and Dickson both take logical truths to be true in virtue of the world’s structure, given by our best empirical theory, quantum mechanics. This assumes a determinate logical structure of the world given by quantum mechanics. Here, I argue that this assumption is false, and that the world’s logical structure, and hence the related ‘true’ logic, is underdetermined. This leads to what I call empirical conventionalism. (shrink)

Logic and philosophy of science share a long history, though contacts have gone through ups and downs. This paper is a brief survey of some major themes in logical studies of empirical theories, including links to computer science and current studies of rational agency. The survey has no new results: we just try to make some things into common knowledge.

There is a certain dominant tradition, school, ambiance or intellectual community in contemporary philosophy of science which can conveniently be labelled logical empiricism. Now a curious and (I believe) hitherto unremarked change occurred in the accepted methodology of logical empiricism shortly after the end of World War II. Before then accepted forms of argument for philosophical theses about the logic, analysis, or rational reconstruction of science fell into two main categories. Some arguments appealed to familiar or historically attestable (...) facts about the development of science, the declared aims of scientists, etc. in certain areas. Others appealed to criteria of generality, clarity, accuracy, consistency, simplicity, and similar considerations of a systematic nature in the construction of philosophical analyses. Appeals were rarely, if ever, made at that time to intuition. If an intuitive idea was mentioned at all, it was mentioned as something that might suggest a starting-point of enquiry but could not be relied upon, even presumptively, as the ground for a conclusion. But this situation changed markedly from the late '40's onwards. Many arguments came to be rested, quite explicitly, on the alleged intuitive acceptability of certain premisses. In the Carnapian school, for example, the guiding objective of an inductive logician seems no longer to be the rational reconstruction of scientific reasoning but rather the axiomatisation of his own intuitions by the most sophisticated methods available. (shrink)

This paper considers the rediscovery of Hegel currently taking place in the analytic philosophy. Going back to the Hegelian texts themselves, I will try to show how they can help to decisively solve some problems of contemporary philosophy. I will concentrate on the theme of knowledge, and especially mathematical knowledge, in relation to Hegelian dialectical logic.

K. R. Popper distinguished between two main uses of logic, the demonstrational one, in mathematical proofs, and the derivational one, in the empirical sciences. These two uses are governed by the following methodological constraints: in mathematical proofs one ought to use minimal logical means (logical minimalism), while in the empirical sciences one ought to use the strongest available logic (logical maximalism). In this paper I discuss whether Popper’s critical rationalism is compatible with a revision of logic in (...) the empirical sciences, given the condition of logical maximalism. Apparently, if one ought to use the strongest logic in the empirical sciences, logic would remain immune to criticism and, thus, non-revisable. I will show that critical rationalism is theoretically compatible with a revision of logic in the empirical sciences. However, a question that remains to be clarified by the critical rationalists is what kind of evidence would lead them to revise the system of logic that underlies a physical theory, such as quantum mechanics? Popper’s falsificationist methodology will be compared with the recently advocated extension of the abductive methodology from the empirical sciences to logic by T. Williamson, since both of them arrive at the same conclusion concerning the status of classical logic. (shrink)

Inductive logic generalizes the idea of logical entailment and provides standards for the evaluation of non-conclusive arguments. A main application of inductive logic is the generalization of observational data to theoretical models. In the empirical sciences, the mathematical theory of statistics addresses the same problem. This paper argues that there is no separable purely logical aspect of statistical inference in a variety of complex problems. Instead, statistical practice is often motivated by decision-theoretic considerations and resembles empirical science.

In this paper, I propose a comparison between some widely accepted Quinian views and Ludwig Wittgenstein's remarks on the logical and the empirical in On Certainty. While Quine's perspective and Wittgenstein's aare not thorougly dissimilar (so that the question of which influence Wittgenstein's thought might have had on the thought of some contemporary philosopher like Quine is both interesting and relevant), there is at least one important difference between them. I submit that Wittgenstein's view on this crucial distinction are (...) more general but ultimately more plausible than the nowadays popular Quinian view. (shrink)

Subintuitionistic (propositional) logics are those in a standard intuitionistic language that result by weakening the frame conditions of the Kripke semantics for intuitionistic logic. In this paper we consider two negation expansions of subintuitionistic logic, one by classical negation and the other by what has been dubbed “empirical” negation. We provide an axiomatization of each expansion and show them sound and strongly complete. We conclude with some final remarks, including avenues for future research.

Empirical Logic and Public Debate supplies a large number of previously unpublished papers that together make up a survey of recent developments in the field of empirical logic. It contains theoretical contributions, some of a more formal and some of an informal nature, as well as numerous contemporary and historical case studies. The book will therefore be attractive both to those who wish to focus upon the theory and practice of discussion, debate, arguing, and argument, as well as to those (...) readers who are primarily interested in applications to a particular field, such as ethics, political philosophy, feminist philosophy, or the history of philosophy. (shrink)

The focus on this volume is on logic and how the logic of foundational hierarchies may be applied to clarify the relationship between sociological theory and empirical research. The author articulates a logical calculus as a method for theory construction.

The following well-known problem motivated my handling more general problems. As we surely know, our pupils and even students are confronted with much more trouble when learning mathematics (and even physics) than when they learn ‘empirical’ sciences like biology, mineralogy etc. There are many factors that can at least partially explain this phenomenon. I would however mention one factor that is not too frequently adduced: mathematics, logic, and much of physics use concepts that are abstract while the empirical sciences seem (...) to support understanding by using expressions concerning (denoting? expressing?) concrete objects. Therefore the first topic to be explained (or explicated) is: Abstract vs. concrete. The second point will consist of applying the first point to explanation of the trouble with learning mathematics. The third point will ask Logical Analysis of Natural Language how to tell abstract expressions from concrete ones. The fourth point will confront the concept described in the foregoing point with conceptions trying to abandon the distinction between analytic and empirical expressions. Here it will be shown that the empiricism representing this latter conception deprives semantics as applied to Natural language of important features of expressivity. (shrink)

This essay offers a new interpretation of Michael Hardt and Antonio Negri’s landmark work of critical social theory Empire. It develops an account of the politics of exile by situating this political strategy in terms of Hardt and Negri’s claim that it is no longer feasible to confront capitalist power head-on. It attends closely to Hardt and Negri’s account of Empire’s pyramidal structure, and the problems that this structure creates for the multitude’s passage from virtuality to actuality. It criticizes the (...) authors’ assertion that, under Empire, the institutions associated with modernity have become indistinguishable from one another in ‘society of control.’ This essay concludes by theorizing the historicity and power of the university, in an attempt to specify what the democratic self-organization of the multitude, together with its exodus from Empire, might look like. Accordingly, it contends that the production of knowledge and higher education depend upon an idea of absolute value which outstrips the commodity-form, and in so doing, provides an intimation of the multitude passing to the exterior of Empire. (shrink)

In this paper, I present two ampliative adaptive logics: LA and LAk. LA is an adaptive logic for abduction that enables one to generate explanatory hypotheses from a set of observational statements and a set of background assumptions. LAk is based on LA and has the peculiar property that it selects those explanatory hypotheses that are empirically most successful. The aim of LAk is to capture the notion of empirical progress as studied by Theo Kuipers.

Exact philosophy consists of various disciplines scattered and separated. Formal semantics and philosophy of science are good examples of two such disciplines. The aim of this paper is to show that there is possible to find some integrating bridge topics between the two fields, and to show how insights from the one are illuminating and suggestive in the other.

It is argued that mathematical statements are "a posteriori synthetic" statements of a very special sort, To be called "structure-Analytic" statements. They follow logically from the axioms defining the mathematical structure they are describing--Provided that these axioms are "consistent". Yet, Consistency of these axioms is an empirical claim: it may be "empirically verifiable" by existence of a finite model, Or may have the nature of an "empirically falsifiable hypothesis" that no contradiction can be derived from the axioms.

In this paper I will investigate the possibility of completing a Positivist style account of demarcation. One reason for pursuing this project is that standard criticisms of Positivism do not have the bite against the demarcation project that they are often assumed to have. To argue this will be the burden of the first part of this paper. The other reason is that new research in logic has provided machinery not available to the Positivists; machinery that shows promise for solving (...) some of the technical problems faced by Positivists' account of demarcation. To argue this will be the burden of the second part of this paper. (shrink)

CONTENTS: 1 Introductory Remark; 2 Formalism of Empirical Theories; 3 Semantics of Formalized Languages; 4 Interpretation of Empirical Theories; 5 Interpretation of Observational Terms; 6 Interpretation of Theoretical Terms; 7 Main Types of Meaning Postulates for Theoretical Terms; 8 Some Other Kinds of Meaning Postulates for Theoretical Terms; 9 Main Types of Statements in an Empirical Theory; 10 Towards a More Realistic Account; 11 Concluding Remarks; 12 Bibliographical Note.

‘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)

CONSIDER A NON EMPTY BUT OTHERWISE ARBITRARY SET OF\nPROPERTIES CALLED OBSERVATION-PROPERTIES (O-PROPERTIES).\nCALL A PROPERTY P A MEANINGFUL PROPERTY (M-PROPERTY) IF IT\nIS EQUIVALENT TO A (FINITE OR INFINITE) DISJUNCTION OF\nO-PROPERTIES--I.E., A NECESSARY AND SUFFICIENT CONDITION\nFOR P IS THAT AT LEAST ONE OBSERVATION-PROPERTY IN A\nCERTAIN SET O(P) BE TRUE. OBVIOUSLY THE CONJUNCTION AND\nDISJUNCTION OF TWO M-PROPERTIES IS AN M-PROPERTY; IN\nGENERAL THE NEGATION OF AN M-PROPERTY IS NOT AN M-PROPERTY.\nHOWEVER WE CAN DEFINE THE PSEUDO NEGATION OF AN M-PROPERTY\nP AS THE POSSESSION OF SOME (...) O-PROPERTY INCOMPATIBLE WITH P.\nTHE ALGEBRA OF DISJUNCTION, CONJUNCTION AND PSEUDO NEGATION\nOF M-PROPERTIES TURNS OUT TO START IN THE SAME RELATION TO\nBOOLEAN ALGEBRA AS INTUITIONISTIC LOGIC (NOT 3-VALUED\nLOGIC) DOES TO CLASSICAL LOGIC, AND SUGGESTS THEREFORE THAT\nINTUITIONISTIC RATHER THAN 3-VALUED LOGIC IS THE\nAPPROPRIATE FORMALISM TO DEAL WITH THE PARADOXES OF THE\nBALD MAN, THE HEAP, ETC. (shrink)