Unification beyond justification: a strategy for theory development

This paper considers the importance of unification in the context of developing scientific theories. I argue that unifying hypotheses are not valuable simply because they are supported by multiple lines of evidence. Instead, they can be valuable because they guide experimental research in different domains in such a way that the results from those experiments inform the scope of the theory being developed. I support this characterization by appealing to the early development of quantum theory. I then draw some comparisons with discussions of robustness reasoning

Old Evidence in the Development of Quantum Theory

In this paper, I evaluate Hartmann & Fitelson’s solution to the Bayesian problem of old evidence by applying it to an early stage in the development of quantum theory. I argue that this case study suggests that whether old evidence is anomalous or not affects its support for a hypothesis. I introduce and defend two formal assumptions to accommodate this idea. This analysis not only explicates an important historical example, but it also shows that the given solution captures the intuitive importance of “surprising” evidence that has previously been problematic in the context of old evidence

Evaluating the Quantum Postulate in the Context of Pursuit

The purpose of this dissertation is to contribute to our understanding of scientific theory pursuit by providing a detailed case study on the development of early quantum theory, from roughly 1900 to 1916. I first elaborate on why this case should be considered an instance of piecemeal pursuit by presenting the historical quantum conjectures that were being used in different contexts. These conjectures gave varied interpretations of quantization. By comparing these conjectures, I identify a general quantum postulate that captures the underlying assumption common to all the cases. I argue that it is possible to consider a general postulate about quantization even when its proper application is ambiguous in a given context, and that the postulate can be separated from different elements of the framework being used to investigate it. I show that the quantum postulate can be deemed promising by analysing the support it gains using a Bayesian framework. I first defend the use of such a framework by considering the purported inconsistencies in Planck\u27s introduction of his quantum conjecture and how we should handle these. I then explicate two cases of support for the postulate. First, I show how we can use a particular solution to the Bayesian problem of old evidence to interpret the support the quantum postulate received by accounting for phenomena that had no previous explanation. Finally, I show that the quantum postulate is also supported by a unification argument, where unification is interpreted as informational relevance between the different domains of inquiry

A New Role for Data in the Philosophy of Science

There exists a problem of the circularity in measurement: construction of theories requires reliable data, but obtaining reliable data requires reliable measurement devices whose construction requires a theory. I argue that adapting Anil Gupta's empiricist epistemology to a scientific context yields a possible solution. One can consider the role of data not as providing a foundation for a theory, but as acting functionally, licensing revisions of a previous theory. Data provide scientists with entitlement to their claims conditional on their background theory. Unconditional entitlement is obtained when different starting theories converge to the same view over the course of experimentation. I explain this idea using two examples, one in thermometry and one involving experiments on the weak neutral current.Il existe un problème de circularité de la mesure : la construction des théories requière des données fiables, mais obtenir des données fiables requière des dispositifs de mesure dont la construction requière une théorie. Je soutiens qu'une possible solution à ce problème peut être trouvée en adaptant l'épistémologie empiriste de Anil Gupta au contexte de la science. On peut considérer les données, non comme un fondement pour la théorie, mais comme jouant un rôle fonctionnel, celui de rendre licite des révisions de la théorie antérieure. Les données autorisent les scientifiques à accepter des énoncés scientifiques sous la condition des théories d'arrière-plan qui sont les leurs. Une autorisation inconditionnelle est obtenue quand les différentes théories de départ convergent sur la même conception au cours de l'expérimentation. J'explique cette idée en utilisant deux exemples, l'un relevant de la thermométrie, l'autre mettant en jeu les expériences sur les courants neutres faibles

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ABSTRACT. Objective. To investigate whether development of systemic lupus erythematosus (SLE), its clinical manifestations, and autoantibody production are associated with polymorphisms of the mannose-binding lectin Conclusion. A significantly increased prevalence of anti-Smith antibody was associated with the heterozygous genotypes A/B and A/C. Although MBL structural gene polymorphism was not a risk factor for SLE development in this study population, homozygosity of MBL variant alleles may be a weak disease-modifying factor, particularly for renal involvement, in North American patients with SLE

Streptococcus intermedius causing infective endocarditis and abscesses: a report of three cases and review of the literature

<p>Abstract</p> <p>Background</p> <p><it>Streptococcus intermedius </it>is a member of the Streptococcus anginosus group. Clinical disease with <it>S. intermedius </it>is characterized by abscess formation and rarely endocarditis. Identification of <it>Streptococcus intermedius </it>is difficult, leading to the development of molecular methods to more accurately identify and characterize this organism.</p> <p>Case presentation</p> <p>Over a period of 6 months we encountered three cases of invasive <it>Streptococcus intermedius </it>infection presenting as hepatic abscesses, brain abscess, and endocarditis. We confirmed our microbiologic diagnosis through 16S sequencing and found a common virulence gene in each case.</p> <p>Conclusion</p> <p>Our report illustrates three different clinical manifestations due to <it>Streptococcus intermedius </it>infection that can be encountered in healthy individuals in a community hospital setting. To our knowledge, this is the first case of <it>Streptococcus intermedius </it>endocarditis confirmed by 16S sequencing analysis. The use of molecular methods may allow a better understanding of the epidemiology and pathogenesis of this organism.</p

Unification and the quantum hypothesis in 1900--1913

In this paper, I consider some of the first appearances of a hypothesis of quantized energy between the years 1900 and 1913 and provide an analysis of the nature of the unificatory power of this hypothesis in a Bayesian framework. I argue that the best way to understand the unification here is in terms of informational relevance: on the assumption of the quantum hypothesis, phenomena that were previously thought to be unrelated turned out to yield information about one another based on agreeing measurements of the numerical value of Planck’s constant

The Role of Hypothesis in the Context of Scientific Theory Pursuit

There has been much discussion arising from Reichenbach\u27s distinction in the philosophy of science between the context of discovery and the context of justification. More recently, some have also begun to distinguish between these and the context of pursuit at which point scientists are pursuing a theory or hypothesis that has been suggested as plausible, but is not yet deemed acceptable. However, there has been relatively little work done on characterizing this process by using specific scientific examples. In this talk, I consider Millikan\u27s 1916 experiment on the photoelectric effect, and its relation to Einstein\u27s light quanta hypothesis in order to clarify the role of hypotheses in the context of theory pursuit. I argue that Millikan\u27s results did not directly support the light quanta hypothesis, but that they did constrain the possible theories that could be subsequently developed. Thus, a hypothesis can be useful for guiding research, but we must be careful to evaluate whether the experimental results genuinely support the hypothesis or not