Philosophers have traditionally conceived of discovery in terms of internal cognitive acts. Close consideration of Rosalind Franklin's role in the discovery of the DNA double helix, however, reveals some problems with this traditional conception. This article argues that defining discovery in terms of mental operations entails problematic conclusions and excludes acts that should fall within the domain of discovery. It proposes that discovery be expanded to include external acts of making visible. Doing so allows for a reevaluation of Franklin's role in the discovery of the structure of DNA.

1. Some Preliminary Distinctions. The relation between the natural and the social sciences, as it bears on their respective subject-matters, methods, and propositions, has long been a source of problems for the philosophy of science. The title of this paper is intended to indicate one of the most basic of these problems. Before developing my point, however, I wish to guard against a possible misinterpretation. I am not questioning the accepted fact that as knowledge in any field advances men may come to recognize the incorrectness of what they had previously regarded as “laws” in that field, and may consequently “change” these laws to take account of such increased knowledge. Let me call this kind of change of laws doctrinal change. The kind of change about which I am asking is rather a change in the subject-matter itself insofar as it is subject to laws—i.e., a change in the causal relations among the facts, objects, properties, events, or whatever they may be called, with which the science deals. Let me call this kind of change of laws factual change. Now, without inquiring more fully at the moment into the nature of scientific laws as such, we may say that the history of science shows that men can and do effect doctrinal changes in the laws of any science, natural as well as social, and formal as well as empirical. And it is recognized also, with minor exceptions to be noted later, that men cannot effect factual changes in the laws of the natural sciences, since these are independent of human volition or decision. The question I am asking, then, is whether men can effect factual changes in the laws of the social sciences.

We revive the idea that a deductive-nomological explanation of a scientific theory by its successor may be defensible, even in those common and troublesome cases where the theories concerned are mutually incompatible; and limiting, approximating and counterfactual assumptions may be required in order to define a logical relation between them. Our solution is based on a general characterization of limiting relations between physical theories using the method of nonstandard analysis.

In two recent papers, I criticized Ronald N. Giere's and Larry Laudan's arguments for ‘naturalizing’ the philosophy of science (Siegel 1989, 1990). Both Giere and Laudan replied to my criticisms (Giere 1989, Laudan 1990b). The key issue arising in both interchanges is these naturalists' embrace of instrumental conceptions of rationality, and their concomitant rejection of non-instrumental conceptions of that key normative notion. In this reply I argue that their accounts of science's rationality as exclusively instrumental fail, and consequently that their cases for ‘normatively naturalizing’ the philosophy of science fail as well.

This study concerns logical systems considered as theories. By searching for the problems which the traditionally given systems may reasonably be intended to solve, we clarify the rationales for the adequacy criteria commonly applied to logical systems. From this point of view there appear to be three basic types of logical systems: those concerned with logical truth; those concerned with logical truth and with logical consequence; and those concerned with deduction per se as well as with logical truth and logical consequence. Adequacy criteria for systems of the first two types include: effectiveness, soundness, completeness, Post completeness, “strong soundness” and strong completeness. Consideration of a logical system as a theory of deduction leads us to attempt to formulate two adequacy criteria for systems of proofs. The first deals with the concept of rigor or “gaplessness” in proofs. The second is a completeness condition for a system of proofs. An historical note at the end of the paper suggests a remarkable parallel between the above hierarchy of systems and the actual historical development of this area of logic.

Philosophers disagree how abstract, theoretical principles can be applied to instances. This paper generates a puzzle for law theorists, causal theorists and inductivists alike. Intractability can force scientists to use a “semi-empirical” method, in which some of an equation's theoretically-determinable parameters are replaced with values taken directly from the data. This is not a purely deductive or inductive process, nor does it involve causes and capacities in any simple way (Humphreys 1995). I argue the predictive successes of such methods require us to reanalyze our views about the nature of prediction, the status of models, and the goal(s) of science. When laws and experimental evidence are neither individually nor jointly sufficient for prediction, models become the locus of understanding. I analyze an historically important debate about the use of semi-empirical methods to construct potential energy surfaces.

This paper considers the relationship between continuum hydrodynamics and discrete molecular dynamics in the context of explaining the behavior of breaking droplets. It is argued that the idealization of a fluid as a continuum is actually essential for a full explanation of the drop breaking phenomenon and that, therefore, the less “fundamental,” emergent hydrodynamical theory plays an ineliminable role in our understanding.

Bogen and Woodward argued the indirect connection between data and theory in terms of their conception of “phenomena.” I outline and elaborate on their presentation. To illuminate the connection with contemporary thinking in terms of models, I distinguish between phenomena tokens, representations of which can be identified with data models, and phenomena types that can be identified with relatively low-lying models or aspects of models in the model hierarchy. Throughout I stress the role of idealization in these considerations.

Definitions of animal welfare often invoke consciousness or sentience. Marian Stamp Dawkins has argued that to define animal welfare this way is a mistake. In Dawkins’s alternative view, an animal with good welfare is one that is healthy and “has what it wants.” The dispute highlights a source of strain on the concept of animal welfare: consciousness-involving definitions are better able to capture the normative significance of welfare, whereas consciousness-free definitions facilitate the validation of welfare indicators. I reflect on how the field should respond to this strain, ultimately recommending against splitting the concept and in favor of consciousness-involving definitions.

In recent years, several authors have called to ground descriptive and normative decision theory on neuropsychological measures of utility. In this article, I combine insights from the best available neuropsychological findings, leading philosophical conceptions of welfare, and contemporary decision theory to rebut these prominent calls. I argue for two claims of general interest to philosophers, choice modelers and policy makers. First, severe conceptual, epistemic, and evidential problems plague ongoing attempts to develop accurate and reliable neuropsychological measures of utility. Second, even if these problems are solved, neuropsychological measures of utility lack the potential to directly inform welfare analyses and policy evaluations.

Newton's methodology is significantly richer than the hypothetico-deductive model. It is informed by a richer ideal of empirical success that requires not just accurate prediction but also accurate measurement of parameters by the predicted phenomena. It accepts theory-mediated measurements and theoretical propositions as guides to research. All of these enrichments are exemplified in the classical response to Mercury's perihelion problem. Contrary to Kuhn, Newton's method endorses the radical transition from his theory to Einstein's. The richer themes of Newton's method are strikingly realized in a challenge to general relativity from a new problem posed by Mercury's perihelion.

Chemists take mechanisms to be an important way of explaining chemical change. I examine the usefulness of the mechanism approach in the recent philosophical literature in explicating the explanatory use of mechanisms by organic chemists. I argue that chemists consider a mechanism to be explanatory because it accounts for the “dynamic process of bringing about” (Tabery 2004, 10) chemical change. For chemists, mechanisms are causal explanations based on interventions that show “how some possibilities depend on others” (Woodward 2003, 375). Only possibilities are achievable because chemists face a number of challenges when they explain by means of a mechanism.

We list, with discussions, various principles of scientific realism, in order to exhibit their diversity and to emphasize certain serious problems of formulation. Ontological and epistemological principles are distinguished. Within the former category, some framed in semantic terms (truth, reference) serve their purpose vis-à-vis instrumentalism (Part 1). They fail, however, to distinguish the realist from a wide variety of (constructional) empiricists. Part 2 seeks purely ontological formulations, so devised that the empiricist cannot reconstruct them from within. The main task here is to characterize “independence of mind”. A pair of notions, “physical invariance” and “anti-determination”, seem to work. They enable us to assess anew “the problem of constructing the physical out of the phenomenal” (yielding certain clarifications demanded by Goodman). Modern cosmology, especially, is seen to present insuperable obstacles to such empiricist approaches to science. The final section on epistemological principles reveals a morass better avoided in favor of an elementary claim about perception, together with a rejection of any absolute observation/theory dichotomy. Finally, a positive, realist notion of “observable-in-principle” is sketched, and it is suggested that, from the perspective of relativistic cosmology, even this defines no boundary to potential knowledge.

In quantum field theory divergent expressions are “discarded”, leaving finite expressions which provide the best predictions anywhere in science. In fact, this “renormalization procedure” involves no mystery or illegitimate operations. This paper explains, in terms accessible to non-experts, how the procedure really works and explores some different ways in which physicists have suggested that one understand it.

Focused correlation compares the degree of association within an evidence set to the degree of association in that evidence set given that some hypothesis is true. Wheeler and Scheines have shown that a difference in incremental confirmation of two evidence sets is robustly tracked by a difference in their focus correlation. In this essay, we generalize that tracking result by allowing for evidence having unequal relevance to the hypothesis. Our result is robust as well, and we retain conditions for bidirectional tracking between incremental confirmation measures and focused correlation.

We lay groundwork for applying ethnographic methods in philosophy of science. We frame our analysis in terms of two tasks: (1) to identify the benefits of an ethnographic approach in philosophy of science and (2) to structure an ethnographic approach for philosophical investigation best adapted to provide information relevant to philosophical interests and epistemic values. To this end, we advocate for a purpose-guided form of cognitive ethnography that mediates between the explanatory and normative interests of philosophy of science, while maintaining openness and independence when framing such an investigation to achieve robust unbiased results.

Paul Griffiths et al. have proposed a quantitative measure of causal specificity and used it to assess various attempts to single out genetic causes as being causally more specific than other cellular mechanisms, for example, alternative splicing. Focusing in particular on developmental processes, they have identified a number of important challenges for this project. In this discussion note, I would like to show how these challenges can be met.

On the critical side it is argued that, contrary to a widespread view, the explanation of particular facts does not play a central role in pure science and hence that philosophers of science are misguided in supposing that the understanding of such explanations is one of the central tasks of the philosophy of science. It is suggested that the view being attacked may stem in part from an impression that the establishing of a general law is tantamount to the explanation of particular facts that “fall under” the law. This suggestion effects a bridge to the more positive part of the paper, which consists of an exploration of the complexities exhibited by the relation between the two activities. More specifically, I point out a number of disabilities, any one of which could prevent us from being able to explain particular facts that fall under a given law even after having established the law. Some of these have to do with the form of the law, and some have to do with our powers of detection vis-à-vis the particular facts in question. The former sort have to do with the ways in which laws may deviate from the strict-necessary-and-sufficient-condition ideal. The latter include the following points. (1) The individual explanatory factors may lie beyond our present powers of detection. (2) The complexity of such factors may be too great for us to be able to interrelate them. (3) We may be unable to apply concepts used in the law to facts in this area (although they are in fact applicable).

Eric Scerri and other authors have acknowledged that the reality of chemical orbitals is not compatible with quantum mechanics. Recently, however, Scerri and Sharon Crasnow have argued that if chemists cannot consider orbitals as real entities, then chemistry is in danger of being reduced to physics. I argue that the question of the existence of orbitals is best viewed as an issue of explanation, not metaphysics: In many chemically important cases orbitals do not make sufficiently accurate predictions, and must be replaced. Chemists and physicists can acknowledge this fact while maintaining the utility of orbitals and the autonomy of chemistry.

Optogenetic techniques are described as “revolutionary” for the unprecedented causal control they allow neuroscientists to exert over neural activity in awake-behaving animals. In this article, I demonstrate by means of a case study that optogenetic techniques will only illuminate causal links between the brain and behavior to the extent that their error characteristics are known and, further, that determining these error characteristics requires (1) comparison of optogenetic techniques with techniques having well-known error characteristics (methodological pluralism) and (2) consideration of the broader neural and behavioral context in which the targets of optogenetic interventions are situated (perspectival pluralism).