Models and structures: Phenomenological and partial

In a recent paper, Suárez and Cartwright (2008) return to the example of London and London's construction of a model for superconductivity and raise a number of concerns against the account of this construction presented in French and Ladyman (1997) and elsewhere. In this discussion note, we examine the challenge they raised and offer our responses.     

Modeling for fairness: A Rawlsian approach

In this paper we introduce the overlapping design consensus for the construction of models in design and the related value judgments. The overlapping design consensus is inspired by Rawls’ overlapping consensus. The overlapping design consensus is a well-informed, mutual agreement among all stakeholders based on fairness. Fairness is respected if all stakeholders’ interests are given due and equal attention. For reaching such fair agreement, we apply Rawls’ original position and reflective equilibrium to modeling. We argue that by striving for the original position, stakeholders expel invalid arguments, hierarchies, unwarranted beliefs, and bargaining effects from influencing the consensus. The reflective equilibrium requires that stakeholders’ beliefs cohere with the final agreement and its justification. Therefore, the overlapping design consensus is not only an agreement to decisions, as most other stakeholder approaches, it is also an agreement to their justification and that this justification is consistent with each stakeholders’ beliefs. For supporting fairness, we argue that fairness qualifies as a maxim in modeling. We furthermore distinguish values embedded in a model from values that are implied by its context of application. Finally, we conclude that for reaching an overlapping design consensus communication about properties of and values related to a model is required.     

Peptide antibiotic biosynthesis: A new approach

Zusammenfassung Eine verallgemeinernde biosynthetische Theorie über die Entstehung vond-Aminosäuren in Peptid-Antibiotika wird dargestellt und zur Bildung von makrozyklischen Strukturen aus kleineren Ring-systemen in Beziehung gesetzt.     

Quantum reality: A pragmaticized neo-Kantian approach

Despite remarkable efforts, it remains notoriously difficult to equip quantum theory with a coherent ontology. Hence, Healey (2017, 12) has recently suggested that “quantum theory has no physical ontology and states no facts about physical objects or events”, and Fuchs et al. (2014, 752) similarly hold that “quantum mechanics itself does not deal directly with the objective world”. While intriguing, these positions either raise the question of how talk of ‘physical reality’ can even remain meaningful, or they must ultimately embrace a hidden variables-view, in tension with their original project. I here offer a neo-Kantian alternative. In particular, I will show how constitutive elements in the sense of Reichenbach (1920) and Friedman (1999, 2001) can be identified within quantum theory, through considerations of symmetries that allow the constitution of a ‘quantum reality’, without invoking any notion of a radically mind-independent reality. The resulting conception will inherit elements from pragmatist and ‘QBist’ approaches, but also differ from them in crucial respects. Furthermore, going beyond the Friedmanian program, I will show how non-fundamental and approximate symmetries can be relevant for identifying constitutive principles.     

A non-linear combination of experts' forecasts: A Bayesian approach

A general Bayesian approach to combining n expert forecasts is developed. Under some moderate assumptions on the distributions of the expert errors, it leads to a consistent, monotonic, quasi-linear average formula. This generalizes Bordley's results.     

A new partial synthesis of holaphyllamine

Résumé L'holaphyllamine peut être aisément préparée à partir du 3, 6-ditosyloxy-5-pregnan-20-one par réaction avec NaN₃.     

Trade-offs in model-building: A more target-oriented approach

In his 1966 paper “The Strategy of model-building in Population Biology”, Richard Levins argues that no single model in population biology can be maximally realistic, precise and general at the same time. This is because these desirable model properties trade-off against one another. Recently, philosophers have developed Levins’ claims, arguing that trade-offs between these desiderata are generated by practical limitations on scientists, or due to formal aspects of models and how they represent the world. However this project is not complete. The trade-offs discussed by Levins had a noticeable effect on modelling in population biology, but not on other sciences. This raises questions regarding why such a difference holds. I claim that in order to explain this finding, we must pay due attention to the properties of the systems, or targets modelled by the different branches of science.     

A simple UV-microbeam for partial cell irradiation

Résumé On peut irradier les régions sous-cellulaires si la radiation UV d'un monochromateur est limitée par les ouvertures interchangeables de champ dans le plan de la pellicule photographique d'un appareil reflex, monté sur un microscope. L'image UV est démagnifiée par un oculaire et un objectif achromatique aussi bien à la lumière UV qu'à la lumière visible.     

A partial elucidation of the gauge principle

The elucidation of the gauge principle “is the most pressing problem in current philosophy of physics” said Michael Redhead in 2003. This paper argues for two points that contribute to this elucidation in the context of Yang–Mills theories. (1) Yang–Mills theories, including quantum electrodynamics, form a class. They should be interpreted together. To focus on electrodynamics is potentially misleading. (2) The essential role of gauge and BRST symmetries is to provide a local field theory that can be quantized and would be equivalent to the quantization of the non-local reduced theory. If this is correct, the gauge symmetry is significant, not so much because it implies ontological consequences, but because it allows us to quantize theories that we would not be able to quantize otherwise. Thus, in the context of Yang–Mills theories, it is essentially a pragmatic principle. This does not seem to be the case for the gauge symmetry in general relativity.     

A facile approach to dihydrojasmone

Résumé La dihydrojasmone a été synthétisée en trois étapes à partir du pentanedione-2,4.

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This research was supported by NRCC, Ottawa.     

Linear combination of forecasts with an intercept: A bayesian approach

The standard approach to combining n expert forecasts involves taking a weighted average. Granger and Ramanathan proposed introducing an intercept term and unnormalized weights. This paper deduces their proposal from Bayesian principles. We find that their formula is equivalent to taking a weighted average of the n expert forecasts plus the decision-maker's prior forecast.     

A mathematical approach to cognitive processes

A mathematical formalization of cognitive processes based on concepts previously given in Experientia is presented. Cognitive processes are described as a set of exponentially decaying interaction probabilities determined by previous interactions between different elements and an association parameter, the inverse of the cognitive stability. The interactions occur in a 'cognitive string' surrounded by a 'cognitive plasma' which carries the contextual information. The 'complexity' of a cognitive process is proportional to time.     

A mathematical approach to cognitive processes

Summary A mathematical formalization of cognitive processes based on concepts previously given in Experientia¹ is presented. Cognitive processes are described as a set of exponentially decaying interaction probabilities determined by previous interactions between different elements and an association parameter, the inverse of the cognitive stability. The interactions occur in a cognitive string surrounded by a cognitive plasma which carries the contextual information. The complexity of a cognitive process is proportional to time.     

A comparative approach to fish respiration

Zusammenfassung Es wird ein Überblick über neuere Forschungen gegeben, die das weite Arbeitsgebiet des Mechanismus der Fischatmung betreffen. Nachdruck wird auf den vergleichenden Standpunkt einer solchen Forschungsarbeit gelegt, wobei gezeigt wird, dass die Wahl besonderer Spezies ein förderndes Licht auf allgemein wichtige Probleme werfen kann, die bei Kiemenuntersuchungen sowohl auf der Makrostrukturstufe wie auf der Ultrastrukturstufe auftreten. Vom physiologischen Standpunkt aus gesehen, erweisen sich einige Arten auf Grund ihrer Lebensweise für experimentelle Untersuchungen ihres Sauerstoffverbrauchs besonders geeignet. Die strukturelle Anordnung des Pumpenmechanismus anderer Arten erleichert wiederum äusserst günstig die Direktmessung des Ventilationsvolumens und anderer mit dem Gasaustausch zusammenhängender Parameter.

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Based on lectures given in Spring 1969 at Duke University (N. Carolina, USA), Universities of Goteborg, Umca and Uppsala (Sweden).     

A choice-semantical approach to theoretical truth

A central topic in the logic of science concerns the proper semantic analysis of theoretical sentences, that is sentences containing theoretical terms. In this paper, we present a novel choice-semantical account of theoretical truth based on the epsilon-term definition of theoretical terms. Specifically, we develop two ways of specifying the truth conditions of theoretical statements in a choice functional semantics, each giving rise to a corresponding logic of such statements. In order to investigate the inferential strength of these logical systems, we provide a translation of each truth definition into a modal definition of theoretical truth. Based on this, we show that the stronger notion of choice-semantical truth captures more adequately our informal semantic understanding of scientific statements.