Richard Jeffrey and Michael Goldstein have both introduced systematic approaches to the structure of opinion changes. For both approaches there are theorems which indicate great generality and width of scope. The main questions addressed here will be to what extent the basic forms of representation are intertranslatable, and how we can conceive of such programs in general.

The unanimity theory is an account of property-level causation requiring that causes raise the probability of their effects in specified test situations. Richard Otte (1981) and others have presented counterexamples in which one property is probabilistically sufficient for at least one other property. Given the continuing discussion (e.g., Cartwright 1989; Cartwright and Dupré 1988; Eells 1988a,b), many apparently think that these problems are minor. By considering the impact of Otte's cases on recent versions of the theory, by raising several new examples, and by criticizing natural replies, I argue that the problems for the unanimity theory are severe.

Modern physics, which had its beginnings in the inclined-plane experiments of Galileo, deals with the measurable aspects of the world about us. The laws and definitions of classical physics are, at least superficially, differential equations in which each variable represents the result of a particular kind of measurement. These variables are usually called physical quantites. Starting from a few general laws and definitions we can derive formally further relations between the physical quantities and their rates of change in space and time. If the original definitions are self-consistent and the original laws accurate, the relations we derive from them should enable us to predict what the numerical result of a certain measurement will be whenever certain other measurements have yielded specified numerical results.

We make two points about dualities in string theory. The first point is that the conception of duality, which we will discuss, meshes with two dual theories being ‘gauge related’ in the general philosophical sense of being physically equivalent. The second point is a result about gauge/gravity duality that shows its relation to gauge symmetries to be subtler than one might expect: each of a certain class of gauge symmetries in the gravity theory, that is, diffeomorphisms, is related to a position-dependent symmetry of the gauge theory.

During the last decade, in 1958 to be precise, an organizational confrontation took place: the essential issue before its membership was this: should the American Sociological Society (ASS) be rechristened the American Sociological Association (ASA). The results of the vote conclusively demonstrated that for a majority of the participants, it was preferable to be known as a group of ASA's rather than a bunch of ASS's.

The complexity and the technical obscurity of the scientific method have rendered science ever likely to be misunderstood both by scientists themselves and by the general public. Difficulties which remain unrecognized constitute the most formidable obstacles to success in any field. There are such difficulties lurking in the treatment which the scientific method accords its subject-matter. In this essay, I propose to point to one such pitfall in the path of the progress of science. By exposing it, something will already be accomplished toward its avoidance and elimination, and the vast public of uninstructed persons will be able to skirt one more confusion in the effort to understand what the scientists are trying to do.

It is shown by means of a simple example that a good explanation of an event is not necessarily corroborated by the occurrence of that event. It is also shown that this contention follows symbolically if an explanation having higher “explicativity” than another is regarded as better.

The multiple-models approach, which has its origins in Levins’s work, is gaining broader acceptance among philosophers. Levins asserted that there is a trade-off between modeling desiderata, which justified the multiple-models approach through two separate justificatory paths. Some attention has been paid to the trade-off thesis, culminating in a paper by Matthewson and Weisberg. However, no attention has been paid to how the trade-off is supposed to justify the multiple-models approach. I argue that a trade-off between generality and precision cannot support one of Levins’s justificatory paths, and I consider what that might mean for the multiple-models approach.

Stanley Stevens draws a useful distinction among ordinal scales, interval scales, and ratio scales. Most recent discussions of confirmation measures have proceeded on the ordinal level of analysis. In this article, I give a more quantitative analysis. In particular, I show that the requirement that our desired confirmation measure be at least an interval measure naturally yields necessary conditions that jointly entail the log-likelihood measure. Thus, I conclude that the log-likelihood measure is the only good candidate interval (or ratio) measure.

Kant's views on the epistemological status of physical science provide an important example of how a philosophical system can be applied to understand the foundation of scientific theories. Michael Friedman has made considerable progress towards elucidating Kant's philosophy of science; in particular, he has argued that Kant viewed Newton's law of universal gravitation as necessary for the possibility of experiencing what Kant called true motion, which is more than the mere relative motion of appearances but is different from Newton's concept of absolute motion. In this context, Friedman has provided an account of how Kant must have viewed Newton's supposed derivation of universal gravitation from Kepler's laws, based on, among other things, Kant's claim that Newton really needed to make extra assumptions in order to derive universal gravitation. In this paper, I argue that Friedman's account is incomplete for three reasons. First, Friedman has overlooked an important aspect of how Newton's third law is applied in the relevant sections of the Principia; as a result, Friedman's account partially misconstrues the relation between the planetary phenomena and the theory of universal gravitation. Second, his account fails to account for Kant's apparent belief that Kepler's laws are only empirically-based rules, even though they seem to be necessary for the derivation of universal gravitation and hence also necessary for Kant's own definition of true motion. Third, Friedman has overlooked some remarks by Kant that indicate that Kant thought the crucial properties of universal gravitation could be known without reference to the empirically determined motions of the planets and hence seemingly without any help from Newton.

I criticize the particular argument for evolutionary progressivism which is based on the concept of a series of “dominant life forms.”

My procedure is to show that there is no rigorous definition for the concept of “dominant life form.”

I examine several attempts to define this concept by Julian Huxley and a new formulation of the concept by G. G. Simpson and show that none of the criteria either of these men develop for determining which groups of organisms can be classified as dominant are adequate to exclude any groups of organisms from the classification. The concept proves so broad as to be meaningless. Since it is a key concept in the particular argument for progressivism that I discuss, the criticism of the concept demonstrates the argument to be invalid.

In this paper, I critically examine Harré and Madden's attempt, largely as it occurs in their Causal Powers, to secure for causes and laws of nature a kind of necessity which although consistent with commonsensical empiricism and anti-idealistic philosophy of science nevertheless runs counter to the humean-positivistic tradition, which denies the existence of any distinctively “natural” or causal necessity. In the course of the paper, I reveal the multifarious nature of their account and show that each part of that account, commonsensical or ontological, is inadequate. I indicate as well how the multifarious nature of the account allows and even encourages an evasive shifting about in the face of adversity, which shifting no doubt contributes to whatever illusion of adequacy is present in their treatment.

Prior to statistical mechanics and especially before the advent of the new quantum mechanics, it was traditionally held, following in the main the Kantian philosophy, that the task of science is to attain a unique quantitative representation of reality. It was thought—and with justifiable zeal—that a scientific discipline is exact to the extent to which a mathematical pattern yielding quantitative relations can be applied to its subject matter. This view was based on the implicit assumptions that functional relatedness conducive to quantitative evaluation is bound to reveal the most generic, and hence, the most essential traits of events.

What I propose to do in the present paper is to clarify critical realism on some crucial points. While such is my primary purpose, I also entertain the hope that logical positivists and pragmatists may be led to see in this form of realism a necessary supplementation to their emphases and insights. I am persuaded that there has been misunderstanding and prejudice at work partly because of verbal phobias in connection with such phrases as the copy-theory, representative perception, transcendence, the subjective, Cartesian dualism, etc., etc. So strong have these accumulated prejudices been that, in America at least, there has been a tendency to outlaw epistemology. I do not find the same situation in England for instance. Here it seems at times as though pragmatism and positivism have consciously “ganged up” against epistemology—in my opinion to the hurt of philosophy. I have the impression that the younger philosophers in America are bewildered and are largely drifting. Under these conditions it is the duty of any one who believes that he has a clear-cut epistemology capable of rising above these verbal phobias to seek to present it as precisely as possible.

D. Miller's demonstrations of the language dependence of truthlikeness raise a profound problem for the claim that scientific progress is objective. In two recent papers (Barnes 1990, 1991) I argue that the objectivity of progress may be grounded on the claim that the aim of science is not merely truth but knowledge; progress thus construed is objective in an epistemic sense. In this paper I construct a new solution to Miller's problem grounded on the notion of “approximate causal explanation” which allows for linguistically invariant progress outside an epistemic context. I suggest that the notion of “approximate causal explanation” provides the resources for a more robust theory of progress than that provided by the notion of “approximate truth.”

If, as may be generally agreed upon, the term science is to be taken to mean verified knowledge, then it has three attributes: (1) the logical and methodological; that is, how we arrive at verified knowledge; (2) the epistemic; that is, the bodies of verified knowledge that have been arrived at; and (3) the sociological; that is, the organization of men by means of which the bodies of knowledge have been arrived at and the method prosecuted.