Online research in philosophy

Over the last twenty years, Bas van Fraassen has developed a “new epistemology”: an attempt to sail between Bayesianism and traditional epistemology. He calls his own alternative “voluntarism”. A constant pillar of his thought is the thought that rationality involves permission rather than obligation. The present paper aims to offer an appraisal of van Fraassen’s conception of rationality. In section 2, I review the Bayesian structural conception of rationality and argue that it has been found wanting. In sections 3 and 4, I analyse van Fraassen’s voluntarism. I raise some objections about van Fraassen’s reliance on prior opinion and argue that the content of a belief matters to its rationality. In section 5, I criticise van Fraassen’s view that inference to the best explanation is incoherent. Finally, in section 6, I take on van Fraassen’s conception of rationality and show that it is too thin to fully capture rational judgement.

A variant of Hilary Putnam's model-theoretic argument against metaphysical realism appears to show that our quantifiers do not determinately range over absolutely everything. This paper argues that some recent attempts to respond to the quantificational skeptic are unsuccessful and offers an alternative response: the key to answering the skeptic is not to refute her argument but to realize that the argument's setup prevents it from being convincing to those it is directed at.

Both sides in the debate about scientific realism have argued that their view provides a better account of actual scientific practice. For example, it has been claimed that the practice of theory conjunction presupposes realism, and that scientists' use of multiple and incompatible models presupposes some form of instrumentalism. Assuming that the practices of science are rational, these conclusions cannot both be right. I argue that neither of them is right, and that, in fact, all scientific practices are compatible with both realism and instrumentalism. I also repudiate van Fraassen's argument to the effect that the instrumentalist account of scientific practice is logically weaker, hence better, than the realist account. In the end, there are no scientific practice arguments on the table that support either side of the debate. It is also noted that the deficiencies of van Fraassen's argument are recapitulated in Putnam's miracle argument for realism. My pessimistic assessment of the state of the debate is reminiscent of Arthur Fine's. However, Fine's argument for the ‘natural ontological attitude’ once again repeats the problems of van Fraassen's and Putnam's arguments.

In The Scientific Image B. C. van Fraassen argues that a theory of explanation ought to take the form of a theory of why-questions, and a theory of this form is what he provides. Van Fraassen's account of explanation is good, as far as it goes. In particular, van Fraassen's theory of why-questions adds considerable illumination to the problem of alternative explanations in psychodynamics. But van Fraassen's theory is incomplete because it ignores those classes of explanations that are answers not to why-questions but to how-questions. In this article I provide a unified theory of explanatory questions that comprehends both how-questions and why-questions, and I show that a question-theoretic approach to explanation can be defended independently of van Fraassen's programme of Constructive Empiricism.

The model-theoretic argument known as Putnam´s paradox threatens our notion of truth with triviality: Almost any world can satisfy almost any theory. Formal argument and intuition are at odds. David Lewis devised a solution according to which the very stucture of the world fixes how it is to be divided into elite classes which determine the reference of any true theory. Three claims are defended: Firstly, Lewis´ proposal must be completed by an account of successful referential intentions. Secondly, contrary to Catherine Elgin´s criticism of Lewis, natural properties corresponding to elite classes may play a role in sound scientific inquiry. Thirdly, despite Bas van Fraassen´s objection that the sceptic cannot consistently maintain doubts about reference, there is a promising sceptical strategy of exploiting Putnam´s results which is answered by Lewis´ account.

I investigate what it means to have an interpretation of our language, how we manage to bestow a determinate interpretation to our utterances, and to which extent our interpretation of the world is determinate. All this is done in dialogue with van Fraassen’s insightful discussion of Putnam’s model-theoretic argument and of scientific structuralism.

Bas van Fraassen has formulated a semantical or model theoretic analysis of the structure of scientific theories. He contrasts his semantical approach with the syntactic approach of the logical positivists and argues that his theory is preferable on a number of grounds. The aims of this paper are threefold. First, a brief description of van Fraassen's approach is presented. Secondly, his theory is compared with that of the logical positivists and, in so doing, the virtues that van Fraassen believes recommend his theory over the positivist theory are identified. Finally, an objection that is positivist in spirit is raised which suggests that, epistemically, his account is indistinguishable from classical historicism.

The model-theoretic argument, which Putnam employs to argue againstmetaphysical realism, has faced serious objections of many realist opponents.Igor Douven in his recent paper offers a new interpretation of the model-theoreticargument, which avoids the previous objections. The purpose of this paper is toshow that Douven's reconstruction of Putnam's argument is not successful, andhence that the realist objections still stand.

Two of Hilary Putnam's model-theoretic arguments against metaphysical realism are examined in detail. One of them is developed as an extension of a model-theoretic argument against mathematical realism based on considerations concerning the so-called Skolem-Paradox in set theory. This argument against mathematical realism is also treated explicitly. The article concentrates on the fine structure of the arguments because most commentators have concentrated on the major premisses of Putnam's argument and especially on his treatment of metaphysical realism. It is shown that the validity of Putnam's arguments is doubtful and that realists are by no means forced to accept the theses Putnam ascribes to them. It is concluded that Putnam fails to give convincing arguments for rejecting mathematical or metaphysical realism. Furthermore, Putnam's internal realism is discussed critically.

Hilary Putnam's argument against metaphysical realism (commonly referred to as the "model theoretic argument") has now enjoyed two decades of discussion.(1) The text is rich and contains variously construable arguments against variously construed philosophical positions. David Lewis isolated one argument and called it "Putnam's Paradox".(2) That argument is clear and concise; so is the paradoxical conclusion it purports to demonstrate; and so is Lewis' paradox-avoiding solution. His solution involves a position I call "anti-nominalism": not only are classes real, but they are divided into arbitrary and 'natural' classes. The natural classes 'carve nature at the joints', being (as other philosophers might say) the extensions of 'real' properties, universals, or Forms.(3) Thus the argument was turned, in effect, into support for a metaphysical realism stronger than Putnam envisaged.