Science progresses if we succeed in rendering the objects of scientific inquiry more comprehensively or more precisely. Popper tries to formalize this venerable idea. According to him the most comprehensive and most precise description of the world is given by the set T of all true statements. A hypothesis comes the closer to T, or has the more verisimilitude, the more true consequences and the fewer false consequences it implies. Popper proposes to order hypotheses by the inclusion relations between the sets of their true and of their false consequences (“truth contents” and “falsity contents”). A partial ordering would permit one to decide whether the substitution of theory t1 by t2 represents scientific progress. But because of the logical relations between the elements of the sets of logical consequences, or contents, false hypotheses cannot be compared. As our theories usually turn out to be false sooner or later, they can seldom be compared as to their verisimilitude and when they can, the result depends only on which theory implies the other and on their truth-values. Popper even tries to define a measure of verisimilitude on the partial ordering. It has to fail for the same reason. In addition he tries to relativize the concept of a content and fails. What is more, any attempt at defining a measure of better or worse correspondence to the whole truth must fail, as there is no justification for saying that any true primitive sentence asserts as much about reality as some other primitive sentence, or more.

It is argued herein that there are two distinct ways in which all observation vocabularies are prejudiced with respect to theory. An argument based on the demands of adequate translation is invoked to show that even the simplest of our observation predicates must display the first and more obvious grade of bias—intensional bias. It is also argued that any observation vocabulary whose predicates are corrigibly applicable must manifest a second and equally serious grade of bias—extensional bias—independently of whatever intensional bias its predicates may or may not have.

I argue that information about the distal causes of moral beliefs, such as evolution, is only relevant for assessing the epistemic status of moral beliefs in cases where we cannot determine whether the proximal processes producing these beliefs are reliable just by examining the properties of these proximal processes. Any investigation into the epistemic status of moral beliefs given their causes should start with a look at proximal causes—not at evolution. I discuss two proximal psychological influences on moral beliefs—disgust and sympathy—to demonstrate the feasibility of drawing epistemic conclusions from an examination of proximal causes alone.

Current discussions of science—both popular and philosophical—often represent the development of science in our civilization as a gradual process of purification from superstitious, religious, and metaphysical elements. This purification is usually presumed to be complete by now—although there may be occasional lapses on the part of individual scientists. That science has changed in character over the centuries is a truism; that it has increasingly loosened ancient ties with magic, religion, and speculative philosophy is an easily substantiated historical thesis. This much admitted, however, an interesting question remains over for discussion: is science by its very nature independent of philosophy? This question has only as much meaning as its two key words (“science” and “philosophy”). According to one common view, “science” would signify some cumulative heritage of methods, principles, and results, while “philosophy” would signify a certain tradition of writings in which the later constantly refer to the earlier, but which otherwise exhibit no discernible uniformity of methods, principles, or results. On this view, then, science is essentially monistic while philosophy is essentially pluralistic.

In this article I explore some statistical difficulties confronting going conceptions of ‘group’ as understood in accounts of group selection. Most such theories require real groups but define the reality of groups in ways that make it impossible to test for their reality. There are alternatives, but they either require or invite a nominalism about groups that many theorists abjure.

To-day economics is considered the most highly developed discipline among the social sciences. Yet, its explanatory and predictive powers are admitted by all hands to be weak compared to those possessed by the physical sciences. This weakness is still frequently explained by apologetic references to the relatively tender age of economic science. This apparently implies that in the normal course of time economics will grow up and achieve the stature and powers of say, physics. The trouble with this argument is that economics is certainly as old as physics. If it lags behind other disciplines in predictive and explanatory powers, lack of time cannot be the cause.

This paper argues that when used judiciously Bayes's law has a role to play in the evaluation of scientific hypotheses. Several examples are presented in which a rational response to evidence requires a judgement whether to apply Bayes's law or whether, for example, to redistribute prior probabilities. The paper concludes that reflection on Bayes's law illustrates how an adequate account of the rational evaluation of hypotheses requires an account of judgement—a point which several philosophers have noted despite few attempts to develop an adequate theory of judgement.

Michael Ruse has offered an interesting and insightful analysis of function statements in biology. The analysis he gives of statements of the form ‘The function of x in z is to do y‘ is :

1. (i) z does y by using x.

2. (ii) y is an adaptation ([4], p. 91).

The first thing to notice about this formulation is the peculiarity of step (ii). There are many cases in which we would naturally say that x was the adaptation, instead of y; or perhaps we might say that everything asserted in step (i) constituted the adaptation. For example, the function of the duck's webbed feet is to enable it to swim. But we would commonly and naturally say that the adaptation was the webbing, not the swimming. It seems to me that Ruse's insistence on the formulation in (ii) points to the major difficulty of his analysis : and understanding what drives him to this unnatural formulation suggests the way out of those difficulties.

Election prediction by means of opinion polling is a rare empirical success story for social science. I examine the details of a prominent case, drawing two lessons of more general interest: (1) Methodology over metaphysics. Traditional metaphysical criteria were not a useful guide to whether successful prediction would be possible; instead, the crucial thing was selecting an effective methodology. (2) Which methodology? Success required sophisticated use of case-specific evidence from opinion polling. The pursuit of explanations via general theory or causal mechanisms, by contrast, turned out to be precisely the wrong path—contrary to much recent philosophy of social science.

Recently philosophers of biology have argued over whether or not Newtonian mechanics provides a useful analogy for thinking about evolutionary theory. For philosophers, the canonical presentation of this analogy is Sober's. Matthen and Ariew and Walsh, Lewins, and Ariew argue that this analogy is deeply wrong-headed. Here I argue that the analogy is indeed useful, however, not in the way it is usually interpreted. The Newtonian analogy depends on having the proper analogue of Newton's First Law. That analogue is what McShea and Brandon call the Zero Force Evolutionary Law (ZFEL). According to the ZFEL, change, not stasis, is the default state of evolutionary systems.

On many science-related policy questions, the public is unable to make informed decisions, because of its inability to make use of knowledge obtained by scientists. Philip Kitcher and James Fishkin have both suggested therefore that on certain science-related issues, public policy should not be decided on by actual democratic vote, but should instead conform to the public’s counterfactual informed democratic decision (CIDD). Indeed, this suggestion underlies Kitcher’s specification of an ideal of a well-ordered science. This article argues that this suggestion misconstrues the normative significance of CIDDs. At most, CIDDs might have epistemic significance, but no authority or legitimizing force.

The concordance of results that are “robust” across multiple scientific modalities is widely considered to play a critical role in the epistemology of science. But what should we make of those cases where such multimodal evidence is discordant? Jacob Stegenga has recently argued that robustness is “worse than useless” in these cases, suggesting that “different kinds of evidence cannot be combined in a coherent way.” In this article I respond to this critique and illustrate the critical methodological role that robustness plays as an aim of scientific inquiry.

The following analysis shows how developments in epistemic logic can play a nontrivial role in cognitive neuroscience. We argue that the striking correspondence between two modes of identification, as distinguished in the epistemic context, and two cognitive systems distinguished by neuroscientific investigation of the visual system (the “where” and “what” systems) is not coincidental, and that it can play a clarificatory role at the most fundamental levels of neuroscientific theory.

This article is about a start-up problem in scientific practice. Specifically, it is about the problem of justifying paleontological correlation—the practice of using fossils to establish time relations among fossiliferous rocks. Paleontological correlation was the key to assembling a geological timescale during the nineteenth century and remains an important practice in stratigraphic geology to this day. Yet contrary to philosophical expectations, this practice lacked a robust theoretical justification during the first half of the nineteenth century. This article examines what this lack of justification amounted to, as well as how the method of paleontological correlation was justified in practice.

Professor Reichenbach's writings have repeatedly called attention to the important rôle which probability statements play in all inquiry, and he has made amply clear that no philosophy of science can be regarded as adequate which does not square its accounts with the problems of probable inference. Recently he has brought together in convenient form many reflections on the methodology of science familiar to readers of his earlier works, and at the same time he has set himself the task of solving many well-known problems of epistemology in terms of his theory of probability. His latest book is therefore of great interest, both because of the light it throws on Professor Reichenbach's own views and because it reveals the power and limitations of one approach to the problems of science. In particular, while it does not add to the details of his theory of probability worked out elsewhere, the applications Professor Reichenbach now makes of it supply fresh clues for judging its import and adequacy. The object of the present essay, therefore, is to expound a number of his views on probability and epistemology, with a view to examining his conclusions and their relevance to the problems he aims to resolve. The discussion will try to determine whether several features of his present views do not follow from assumptions which he has not sufficiently considered; whether his logical constructions do not create new puzzles; and whether a different starting-point should not be taken if the clarification of scientific concepts and procedures, to which Professor Reichenbach's devotion is as unexcelled as it is well known, is to be successfully conducted.

Biological foundations of the psychoneural identity hypothesis are explicated and their implications discussed. “Consciousness per se” and phenomenal contents of consciousness per se are seen to be identical with events in the (unobserved) brain in accordance with Leibniz's Law, but only informationally equivalent to neural events as observed. Phenomenal content potentially is recoverable by empirical means from observed neural events, but the converse is not possible. Consciousness per se is identical with events which do not represent anything distal to sensory receptor-transducer systems. Thus, on the psychoneural identity hypothesis, consciousness per se comprises directly physical events-in-themselves rather than being a Euclidean representation of physical events as is the case for phenomenal content. After comparing consciousness per se to “onta,” a paradox is suggested: rather than being irreducible to physical reality, consciousness per se is the only experience congruent with the ultimate nature of physical reality as conceived by contemporary physics.

Problems raised by complex life cycles for standard summaries of evolutionary processes, and for concepts of individuality in biology, are described. I then outline a framework that can be used to compare life cycles. This framework treats reproduction as a combination of production and recurrence and organizes life cycles according to the distribution of steps in which multiplication, bottlenecks, and sex occur. I also discuss fitness and its measurement in complex life cycles and consider some phenomena that raise complications and difficulties for my framework.

The current antireductionist consensus rests in part on the indefensibility of the deductive-nomological model of explanation, on which classical reductionism depends. I argue that the DN model is inessential to the reductionist program and that mechanism provides a better framework for thinking about reductionism. This runs counter to the contemporary mechanists’ claim that mechanism is an alternative to reductionism. I demonstrate that mechanists are committed to reductionism, as evidenced by the historical roots of the contemporary mechanist program. This view shares certain core commitments with reductionism. It is these shared commitments that constitute the essential elements of the reductionist program.

The literature of economic theory, like that of philosophy, abounds in prefaces and prolegomena. Methodology and analysis of concepts take an important place in a science which has not found the sure path of development. But there is no sure path for methodology either. The selfconscious methodology of social science has been largely a borrowing from that of physical science, where procedures have developed to a stage of considerable maturity. But the analogy falls down where guidance is most needed, at the points where social science is most likely to develop new concepts and new types of structure. Philosophers have not been lacking, indeed, to belittle the entire enterprise, and to deny the possibility of anything that could strictly be called social science.