Selectionist evolutionary theory has often been faulted for not making novel predictions that are surprising, risky, and correct. I argue that it in fact exhibits the theoretical virtue of predictive capacity in addition to two other virtues: explanatory unification and model fitting. Two case studies show the predictive capacity of selectionist evolutionary theory: parallel evolutionary change in E. coli, and the origin of eukaryotic cells through endosymbiosis.

The thesis of theory-ladenness of observations, in its various guises, is widely considered as either ill-conceived or harmless to the rationality of science. The latter view rests partly on the work of the proponents of New Experimentalism who have argued, among other things, that experimental practices are efficient in guarding against any epistemological threat posed by theory-ladenness. In this paper I show that one can generate a thesis of theory-ladenness for experimental practices from an influential New Experimentalist account. The notion (...) I introduce for this purpose is the concept of ‘theory-driven data reliability judgments’, according to which theories which are sought to be tested with a particular set of data guide reliability judgments about those very same data. I provide various prominent historical examples to show that TDRs are used by scientists to resolve data conflicts. I argue that the rationality of the practices which employ TDRs can be saved if the independent support of the theories driving TDRs is construed in a particular way. (shrink)

El presente escrito se propone presentar el modelo de tres niveles del conocimiento científico (datos, fenómenos y teorías) desde los recientes resultados de la filosofía de la ciencia obtenidos por dos perspectivas filosóficas particulares: el nuevo experimentalismo y el enfoque semántico de las teorías. Para ello contrasta los planteamientos principales de estas dos perspectivas con el modelo de dos niveles del conocimiento científico (observación y teoría) del positivismo lógico, que dominó el panorama de la filosofía de la ciencia en las (...) primeras seis décadas del siglo XX. (shrink)

Exploratory factor analysis is a statistical method widely used in quantitative psychology for the construction of scales and measurement instruments. It aims to reduce the complexity of a data set and explain the common and unique variance using latent variables. In introductory textbooks, exploratory factor analysis is generally presented in contrast to confirmatory factor analysis as a theory- or a hypothesis-generating process that does not require prior background, theory or hypothesis to be performed. The aim of the present paper is (...) to analyze this claim and clarify in which sense exploratory factor analysis is theory-laden. We provide a careful examination of the concepts it involves and thereby establish a clear limitation of the epistemic scope of exploratory factor analysis. (shrink)

A notion of experimental series is developed, in which experiments or experimental sets are connected through experimental suggestions arising from previous experimental outcomes. To that end, the justification of Howard Temin’s DNA provirus hypothesis is examined. The hypothesis originated with evidence from two exploratory experimental sets on an oncogenic virus and was substantiated by including evidence from three additional experimental sets. Collectively these sets comprise an experimental series and the accumulative evidence from the series was adequate to justify the hypothesis (...) by persuading the virology community of its veracity. The notion of crucial experiment is also discussed in terms of experimental series. (shrink)

A notion of experimental series is developed, in which experiments or experimental sets are connected through experimental suggestions arising from previous experimental outcomes. To that end, the justification of Howard Temin's DNA provirus hypothesis is examined. The hypothesis originated with evidence from two exploratory experimental sets on an oncogenic virus and was substantiated by including evidence from three additional experimental sets. Collectively these sets comprise an experimental series and the accumulative evidence from the series was adequate to justify the hypothesis (...) by persuading the virology community of its veracity. The notion of crucial experiment is also discussed in terms of experimental series. (shrink)

El presente escrito se propone presentar el modelo de tres niveles del conocimiento científico (datos, fenómenos y teorías) desde los recientes resultados de la filosofía de la ciencia obtenidos por dos perspectivas filosóficas particulares: el nuevo experimentalismo y el enfoque semántico de las teorías. Para ello contrasta los planteamientos principales de estas dos perspectivas con el modelo de dos niveles del conocimiento científico (observación y teoría) del positivismo lógico, que dominó el panorama de la filosofía de la ciencia en las (...) primeras seis décadas del siglo XX. (shrink)

Philosophers of science diverge on the question what drives the growth of scientific knowledge. Most of the twentieth century was dominated by the notion that theories propel that growth whereas experiments play secondary roles of operating within the theoretical framework or testing theoretical predictions. New experimentalism, a school of thought pioneered by Ian Hacking in the early 1980s, challenged this view by arguing that theory-free exploratory experimentation may in many cases effectively probe nature and potentially spawn higher evidence-based theories. Because (...) theories are often powerless to envisage workings of complex biological systems, theory-independent experimentation is common in the life sciences. Some such experiments are triggered by compelling observation, others are prompted by innovative techniques or instruments, whereas different investigations query big data to identify regularities and underlying organizing principles. A distinct fourth type of experiments is motivated by a major question. Here I describe two question-guided experimental discoveries in biochemistry: the cyclic adenosine monophosphate mediator of hormone action and the ubiquitin-mediated system of protein degradation. Lacking underlying theories, antecedent data bases, or new techniques, the sole guides of the two discoveries were respective substantial questions. Both research projects were similarly instigated by theory-free exploratory experimentation and continued in alternating phases of results-based interim working hypotheses, their examination by experiment, provisional hypotheses again, and so on. These two cases designate theory-free, question-guided, stepwise biochemical investigations as a distinct subtype of the new experimentalism mode of scientific enquiry. (shrink)

In this work, I examine the roles of the experimental background (effects capable of mimicking the one under study) in cognition, and its relation to the problem of closedness of experimental system. Taking as examples the experiments in particle physics widely discussed in the philosophy of science (discoveries of muon and neutral currents), I suggest that determination of the experimental background often implies an explicit use of components of high-level theories. I argue that the neutron background in the neutral current (...) experiments resulted from the same sort of phenomena as the events in the detector did although those phenomena occurred in the materials surrounding the detector rather than in the detector itself. Therefore, it is justified herein that due to the presence of background experimental outcomes are entertained with theory of phenomenon. (shrink)

Focusing on the discovery of weak currents, the current debate on the theory-ladenness of observation in modern physics might be too narrow, as it concerns only the last stage of a complex experimental process and statistical methods required to analyze data. The scope of the debate should be extended to include broader experimental conditions that concern the design of the apparatus and different levels of the detection process. These neglected conditions often decisively delimit experiments long before the last stage has (...) been reached, thus predetermining the extent of the dependence of data production on the theory. I explain the nature of these conditions and the theory-ladenness tendencies they produce, noting how they affect the last stage of the data analysis and providing some relevant examples. (shrink)