In this comprehensive work on theories of rationality, Leslie Allan builds on the seminal insights of Imre Lakatos. Allan begins by critically reviewing Lakatos' theory of rationality (MSRP) and his meta-theory of rationality (MHRP) and suggesting improvements to his scheme. Allan's main task is developing a theory of rationality that avoids Lakatos' Achilles' heel; the presupposition that science is a rational enterprise. To achieve this, he attempts to draw out from the general demands of an objectivist epistemology the various criteria (...) of dependence and independence applying to evidence-statements. He concludes by considering two serious objections to his framework. (shrink)

The author challenges both the eliminative idealist's contention that physical objects do not exist and the phenomenalist idealist's view that statements about physical objects are translatable into statements about private mental experiences. Firstly, he details how phenomenalist translations are parasitic on the realist assumption that physical objects exist independently of experience. Secondly, the author confronts eliminative idealism head on by exposing its heuristic sterility in contrast with realism's predictive success.

Drawing on insights from Imre Lakatos' seminal work on theories of rationality, Leslie Allan develops seven criteria for rational theory choice that avoid presuming the rationality of the scientific enterprise. He shows how his axioms of rationality follow from the general demands of an objectivist epistemology. Allan concludes by considering two weighty objections to his framework.

Imre Lakatos holds a well-deserved primary place in current philosophy of science. In this essay, Leslie Allan critically examines Lakatos' theory of knowledge in two key areas. The first area of consideration is Lakatos' notion that knowledge is gained through a process of competition between rival scientific research programmes. Allan identifies and discusses four problems with Lakatos' characterization of a research programme. Next, Allan considers Lakatos' proposed test of adequacy for theories of rationality using his methodology of historiographical research programmes. (...) Allan discovers tensions within Lakatos' criteria and suggests ways of strengthening his test. (shrink)

The paper examines the role played by the notion of truth in the version of scientific realism known as scientific entity realism. Scientific entity realism is the thesis that the unobservable entities postulated by scientific theories are real. As such, it is an ontological thesis about the existence of certain entities. By contrast, scientific realism is often characterised as a thesis primarily involving the truth of theories. Sometimes scientific realism is expressed as the thesis that theoretical statements are intended as (...) true descriptions of reality. Another favoured theme is that theoretical statements are objectively true or false in virtue of the way the world is independently of us. To such formulations it is usually added that the sense of 'true' required by scientific realism is the correspondence sense. To mark the contrast with scientific entity realism, I shall say that a formulation of scientific realism in terms of truth is a semantic version of scientific realism. [For footnotes, see The Semantic Stance of Scientific Entity Realism Corrigenda in Philosophia 25 3-4 1997 481-482]. (shrink)

A paper on how to adapt your probabilisitc beliefs when learning a conditional.

Four Basic Logical Issues: The paper addresses what we see as the four major issues in logic. The overriding issue is that of the choice of logic. We start with some discussion of the preliminary issue of whether there is such a 'one true logic,' but we reserve the main discussion for the first issue of 'classical logic versus nonclassical logic.' Here, we discuss the role of meaning and truth, the relation between classical logic and classical negation, and whether and, (...) if so, how classical logic should reside at the base world. Given the argument in favor of an overall use of nonclassical logic, the second issue is that of the choice of nonclassical logic. Brady's logic MC of meaning containment is argued for, with some comparison made with other relevant logics. For the remaining two issues, we make a case for relevant deduction, in comparison with classical deduction, and we explore possibilities for the appropriate metalogic, comparing classical and nonclassical approaches. (shrink)

David Hull's (1988c) model of science as a selection process suffers from a two-fold inability: (a) to ascertain when a lineage of theories has been established; i.e., when theories are descendants of older theories or are novelties, and what counts as a distinct lineage; and (b) to specify what the scientific analogue is of genotype and phenotype. This paper seeks to clarify these issues and to propose an abstract model of theories analogous to particulate genetic structure, in order to reconstruct (...) relationships of descent and identity. (shrink)

This paper is obsolete. It is superseded by the book, Conditionals in Context, MIT Press, 2005.

I argue in this paper that anyone who accepts the ontology of scientific realism can only accept a pragmatic theory of truth, i.e., a theory on which truth is what it is epistemically right to believe. But the combination of realism with such a theory of truth is a form of internal realism; therefore, a scientific realist should be an internal realist. The strategy of the paper is to argue that there is no adequate semantic or correspondence theory of truth (...) compatible with a realist ontology, that a redundancy theory cannot account for the value of truth, and that the only kind of truth theory which can account for the value of truth, and is compatible with a realist ontology, is a pragmatic theory. The kind of truth theory I wish to defend is objective and naturalistic, and the ontology is realistic. My position is, therefore, one of objective, naturalistic realism. (shrink)

How to accept a conditional? F. P. Ramsey proposed the following test in (Ramsey 1990).(RT) If A, then B must be accepted with respect to the current epistemic state iff the minimal hypothetical change of it needed to accept A also requires accepting B.

In the face of argument to the contrary, it is shown that there is defensible middle ground available for entity realism, between the extremes of scientific realism and empiricist antirealism. Cartwright's ([1983]) earlier argument for defensible middle ground between these extremes, which depended crucially on the viability of an underdeveloped distinction between inference to the best explanation (IBE) and inference to the most probable cause (IPC), is examined and its defects are identified. The relationship between IBE and IPC is clarified (...) and a revised version of Cartwright's argument for defensible middle ground, which is free of the identified defects, is presented. (shrink)

These are the footnotes for the article which was published in Philosophia Vol 24 1995, pp. 405-415.

The object of this paper is to show why recent research in the psychology of deductive and probabilistic reasoning does not have.

I argue that there are living and everyday case in which rationality requires you, as a non-idealized human thinker, to have inconsistent beliefs while recognizing the inconsistency. I defend my argument against classical and insightful objections by Doris Olin, as well as others. I consider three versions of the preface paradox as candidate cases, including Makinson’s original version. None is free from objection. However, there is a fourth version, Modesty, that supposes that you believe that at least one of your (...) beliefs is false. I argue that this version escapes all the objections that could trouble the other versions, including the objection that given certain closure principles for justified belief, justified inconsistent beliefs saddle you with a pair of justified beliefs that are in explicit contradiction. I also argue more tentatively for the same verdict for Modesty*, a version that supposes that you believe that at least one of your beliefs is false. In that case, your belief guarantees that its content is true, in which case your beliefs are inconsistent, because at least one of them must be false. Once you think you’re wrong, you must be right! Crucial to my argument is a distinction between explicitly contradictory beliefs and three forms of inconsistency in belief. In the first of these, you believe contingent propositions each of which is logically independent of the others, yet you also believe the syntactic negation of their conjunction. In the second, your beliefs are inconsistent because of the rigid designation of demonstratives such as ‘this’ embedded in their contents. In the third, as in Modesty and Modesty* your beliefs are inconsistent because of self-reference. (shrink)

A polemical account of Australian philosophy up to 2003, emphasising its unique aspects (such as commitment to realism) and the connections between philosophers' views and their lives. Topics include early idealism, the dominance of John Anderson in Sydney, the Orr case, Catholic scholasticism, Melbourne Wittgensteinianism, philosophy of science, the Sydney disturbances of the 1970s, Francofeminism, environmental philosophy, the philosophy of law and Mabo, ethics and Peter Singer. Realist theories especially praised are David Armstrong's on universals, David Stove's on logical probability (...) and the ethical realism of Rai Gaita and Catholic philosophers. In addition to strict philosophy, the book treats non-religious moral traditions to train virtue, such as Freemasonry, civics education and the Greek and Roman classics. (shrink)

Probabilistic coherence is not an absolute requirement of rationality; nevertheless, it is an ideal of rationality with substantive normative import. An idealized rational agent who avoided making implicit logical errors in forming his preferences would be coherent. In response to the challenge, recently made by epistemologists such as Foley and Plantinga, that appeals to ideal rationality render probabilism either irrelevant or implausible, I argue that idealized requirements can be normatively relevant even when the ideals are unattainable, so long as they (...) define a structure that links imperfect and perfect rationality in a way that enables us to make sense of the notion of better approximations to the ideal. I then analyze the notion of approximation to the ideal of coherence by developing a generalized theory of belief functions that allows for incoherence, and showing how such belief functions can be ordered with regard to greater or lesser coherence. (shrink)

The realist programme has degenerated by now to the point where it is quite beyond salvage. A token of this degeneration is that there are altogether too many realisms. It is as though by splitting into a confusing array of types and kinds, realism has hoped that some one variety might yet escape extinct. I shall survey the debate, and some of these realisms, below. Here I would just point out the obvious; that in so far as the successes of (...) science mount while realism continues to decline we must conclude that scientific success lends no support to realism. Since it is unlikely to support anti-realism, we have some reason to suspect that the philosophical debate over realism does not concern issues that can be settled by developments in the sciences, no matter how successful science may be. Further, since that success grounds a culture of acceptance for science and its entities, we have reason to believe that the existence of those entities is also not actually the issue that concerns realism. Afortiori, it is not the issue that concerns anti-realism either; nor, I might add, is anti-realism the winner in the philosophical debate that realism has lost. (shrink)

This paper addresses the question whether the past couple of decades of formal research in belief revision offers evidence of a new psychologism in logic. In the first part I examine five potential arguments in favour of this thesis and find them all wanting. In the second part of the paper I argue that belief revision research has climbed up a hierarchy of models for the change of doxastic states that appear to be clearly normative at the bottom, but are (...) more amenable to an empirical-descriptive interpretation on higher levels. I conclude that this observation might offer a foothold for the thesis that there is a new psychologism in logic. (shrink)

This is a defense of the doctrine of scientific realism. SR is defined through the following two claims: Most essential unobservables posited by the well-established current scientific theories exist independently of our minds. We know our well-established scientific theories to be approximately true. I first offer positive argumentation for SR. I begin with the so-called 'success arguments' for SR: 1) scientific theories most of the times entail successful predictions; 2) science is methodologically successful in generating empirically successful theories. SR explains (...) these facts via inference to the best explanation. I combine Hacking's experimental argument for entity realism with Salmon's common-cause principle. I take entity realism to be foundational to SR: one may believe in the existence of some theoretical entities without believing in any particular theory in which these are embedded. Its motivation comes from experimental practice, where the manipulation of these entities often relies on incompatible theoretical accounts. The underdetermination topic is thereafter discussed. Several attempts to distinguish between an observable and an unobservable realm are critically discussed, as well as the possibility that for any given theory, there are empirically equivalents generated by means of algorithms. I present extensive argumentation to the effect that such algorithmic rivals are not to be taken seriously. Social constructivism is being critically treated. I proceed by distinguishing between a metaphysical, a semantic, and an epistemic variant of SC. I conclude that only a moderate metaphysical constructivism can stand on its own feet. Its claim is merely that some facts about the world are socially constructed. I finish with a plea for a selective SR, able to do justice to the presence of both instrumentalism and modest constructivism in scientific practice. (shrink)