In this book van Fraassen develops an alternative to scientific realism by constructing and evaluating three mutually reinforcing theories.

James Ladyman has argued that constructive empiricism entails modal realism, and that this renders constructive empiricism untenable. We maintain that constructive empiricism is compatible with modal nominalism. Although the central term 'observable' has been analyzed in terms of counterfactuals, and in general counterfactuals do not have objective truth conditions, the property of being observable is not a modal property, and hence there are objective, non-modal facts about what is observable. Both modal nominalism and constructive empiricism require clarification in the face (...) of Ladyman's argument. But we also argue that, even if Ladyman were right that constructive empiricism entails modal realism, this would not be a problem for constructive empiricism. (shrink)

After Hume, attempts to forge an empiricist epistemology have taken three forms, which I shall call the First, Middle, and Third Way. The First still attempts an a priori demonstration that our cognitive methods satisfy some criterion of adequacy. The Middle Way is pursued under the banners of naturalism and scientific realism, and aims at the same conclusion on non-apriori grounds. After arguing that both fail, I shall describe the general characteristics of the Third Way, an alternative epistemology suitable for (...) empiricism. (shrink)

A general form is proposed for epistemological theories, the relevant factors being: the family of epistemic judgments, the epistemic state, the epistemic commitment, and the family of possible epistemic inputs. First a simple theory is examined in which the states are probability functions, and the subject of probability kinematics introduced by Richard Jeffrey is explored. Then a second theory is examined in which the state has as constituents a body of information and a recipe that determines the accepted epistemic judgments (...) on the basis of this corpus. Through an examination of several approaches to the statistical syllogism, a relation is again established with Jeffrey's generalized conditionalization. (shrink)

I exist, but I am not a thing among things; X exists if and only if there is something such that it=X. This is consistent, and it is a view that can be supported. Calvino’s novel The Non‐Existent Knight can be read so as to illustrate this view. But what is my relation to the things there are if I am not identical with any of them – things such as my arms, my garden, the city I live in? I (...) name this the Gurduloo problem, after the Knight’s page. This relation must be one that admits of degrees; I suggest that we say that I manifest myself through the things thus associated with me. Several pseudo‐problems, pertaining to volitional action, supervenience, observability, and the emergence of consciousness, dissolve upon inspection. (shrink)

The world science describes tends to have a very strange look. We can’t see atoms or force fields, nor are they imaginable within visualizable categories, so neither can we even imagine what the world must be like according to recent physical theories. That tension, between what science depicts as reality and how things appear to us, though it is more striking now, has been with us since modern science began. It can be addressed, and perhaps alleviated by inquiring into how (...) science represents nature. In general, representation is selective, the selection is of what is relevant to the purpose at hand, and success may even require distortion. From this point of view, the constraint on science, that it must ‘save the phenomena’, takes on a new form. The question to be faced is how the perspectival character of the appearances (that is, contents of measurement outcomes) can be related to the hidden structure that the sciences postulate. In the competing interpretations of quantum mechanics we can see how certain traditional ideals and constraints are left behind. Specifically, Carlo Rovelli’s Relational Quantum Mechanics offers a probative example of the freedom of scientific representation. (shrink)

This collection of essays is dedicated to 'Joe' Karel Lambert. The contributors are all personally affected to Joe in some way or other, but they are definitely not the only ones. Whatever excuses there are - there are some -, the editors apologize to whomever they have neglected. But even so the collection displays how influential Karel Lambert has been, personally and through his teaching and his writings. The display is in alphabetical order - with one exception: Bas van Fraassen, (...) being about the earliest student of Karel Lambert, opens the collection with some reminiscences. Naturally, one of the focal points of this volume is Lambert's logical thinking and (or: freed of) ontological thinking. Free logic is intimately connected with description theory. Bas van Fraassen gives a survey of the development of the area, and Charles Daniels points to difficulties with definite descriptions in modal contexts and stories. Peter Woodruff addresses the relation between free logic and supervaluation semantics, presenting a novel condition which recovers desirable metatheoretic properties for free logic under that semantics. Terence Parsons shows how free logic can be utilized in interpreting sentences as purporting to denote events (true ones succeed and false ones fail) and how this helps to understand natural language. (shrink)

In response to parts I-III of G Rosen's "What is Constructive Empiricism?", "Philosophical Studies", 74, 1994, 143-178, this paper examines several construals of the position of constructive empiricism. At issue, in part, is the equation of intentional aspects of science with the intentions and opinions of scientists. In addition it is necessary to distinguish the constructive empiricist -- a philosopher holding that acceptance of theories in science need not involve belief that they are true -- from the scientific agnostic' who (...) accepts but does not believe current science. What is at stake for empiricism is a view of science that will admit it as a paradigm for rational inquiry. (shrink)

Vague subjective probability may be modeled by means of a set of probability functions, so that the represented opinion has only a lower and upper bound. The standard rule of conditionalization can be straightforwardly adapted to this. But this combination has difficulties which, though well known in the technical literature, have not been given sufficient attention in probabilist or Bayesian epistemology. Specifically, updating on apparently irrelevant bits of news can be destructive of one’s explicitly prior expectations. Stability of vague subjective (...) opinion appears to need a more complex model. (shrink)

The story of how Perrin’s experimental work established the reality of atoms and molecules has been a staple in (realist) philosophy of science writings (Wesley Salmon, Clark Glymour, Peter Achinstein, Penelope Maddy, …). I’ll argue that how this story is told distorts both what the work was and its significance, and draw morals for the understanding of how theories can be or fail to be empirically grounded.

Sentences attributing beliefs, doubts, wants, and the like (propositional attitudes, in Russell's terminology) have posed a major problem for semantics. Recently the pragmatic description of language has become more systematic. I shall discuss the formalization of pragmatics, and propose an analysis of belief attribution that avoids some main problems apparently inherent in the semantic approach.

The modal interpretation of quantum mechanics has two variants: the Copenhagen variant (CV) and the anti-Copenhagen variant (ACV). Healey uses the Bell-Wigner locality condition to criticize the latter, which I do not advocate. 2 The conclusions of Healey's admirably written article are therefore welcome to me. But if I had wished to advocate the ACV, I do not think that his arguments would have dissuaded me. Specifically, as I shall explain, we should distinguish between Physical Locality and Metaphysical Locality. The (...) first principle is unexceptionable, but Healey needs the second for his reductio. At the end I shall briefly indicate why I reject the ACV and advocate instead the Copenhagen variant. (shrink)

Thomason (1979/2010)’s argument against competence psychologism in semantics envisages a representation of a subject’s competence as follows: he understands his own language in the sense that he can identify the semantic content of each of its sentences, which requires that the relation between expression and content be recursive. Then if the scientist constructs a theory that is meant to represent the body of the subject’s beliefs, construed as assent to the content of the pertinent sentences, and that theory satisfies certain (...) ‘natural assumptions’, then it implies that the subject is inconsistent if the beliefs include arithmetic. I challenge the result by insisting that the motivation for Thomason’s principle (ii), via Moore’s Paradox, leads to a more complex representation, in which stating the facts and expressing one’s beliefs are treated differently. Certain logical connections among expressions of assent, and between expression and statement, are a matter of consequence on pain of pragmatic incoherence, not consequence on pain of classical logical inconsistency. But while this salvages the possibility that a modification of the above sort of representation could be adequate, Thomason’s devastating conclusion returns if the scientist identifies himself as the subject of that representation, even when paying heed to the requirement of pragmatic coherence of the sort highlighted by Moore’s Paradox. (shrink)