Observation, Misc

In this article I examine two mathematical definitions of observational equivalence, one proposed by Charlotte Werndl and based on manifest isomorphism, and the other based on Ornstein and Weiss’s ε-congruence. I argue, for two related reasons, that neither can function as a purely mathematical definition of observational equivalence. First, each definition permits of counterexamples; second, overcoming these counterexamples will introduce non-mathematical premises about the systems in question. Accordingly, the prospects for a broadly applicable and purely mathematical definition of observational equivalence (...) are unpromising. Despite this critique, I suggest that Werndl’s proposals are valuable because they clarify the distinction between provable and unprovable elements in arguments for observational equivalence. (shrink)

The physics literature contains many claims that ultrashort-lived unstable particles have been observed. These claims are purely a matter of applying the so-called 5-sigma convention in particle physics: an observation of an ultrashort-lived unstable particle can be claimed when its predicted decay products have been observed with a significance of 5 sigma. This paper critically assesses these observational claims by rigorously analyzing this 5 sigma convention in a frame for modal propositional logic, in which Kripke possible worlds semantics represent a (...) real-world meaning. This analysis establishes as a fact that the condition laid down in the 5 sigma convention is insufficient for an observational claim: one cannot ever claim the observation of a short-lived unstable particle, not even if its predicted decay products have been observed with the required significance. The main implication is that such observational claims have to be dismissed as overstatements: these are misleading and should be retracted. A further implication is expressed by two incompleteness theorems for physics, respectively stating (i) that experiments cannot prove completeness of a physical theory predicting ultrashort-lived unstable particles, and (ii) that experiments cannot prove correctness of such a theory---one can at most test its empirical adequacy. On a general note, the conclusion is that the importance of analytical-philosophical arguments for physics is herewith demonstrated. (shrink)

As data-intensive and computational science become increasingly established as the dominant mode of conducting scientific research, visualisations of data and of the outcomes of science become increasingly prominent in mediating knowledge in the scientific arena. This position piece advocates that more attention should be paid to the epistemological role of visualisations beyond their being a cognitive aid to understanding, but as playing a crucial role in the formation of evidence for scientific claims. The new generation of computational and informational visualisations (...) and imaging techniques challenges the philosophy of science to re-think its position on three key distinctions: the qualitative/quantitative distinction, the subjective/objective distinction, and the causal/non-causal distinction. (shrink)

This paper aims at contributing to the ongoing efforts to get a firmer grasp of the systematic significance of the entanglement of idealism and empiricism in Helmholtz's work. Contrary to existing analyses, however, the focal point of the present exposition is Helmholtz's attempt to articulate a psychological account of objectification. Helmholtz's motive, as well as his solution to the problem of the object are outlined, and interpreted against the background of his scientific practice on the one hand, and that of (...) empiricist and (transcendental) idealist analyses of experience on the other. The specifically psychological angle taken, not only prompts us to consider figures who have hitherto been treated as having only minor import for Helmholtz interpretation (most importantly J.S. Mill and J.G. Fichte), it furthermore sheds new light on some central tenets of the latter's psychological stance that have hitherto remained underappreciated. For one thing, this analysis reveals an explicit voluntarist tendency in Helmholtz's psychological theory. In conclusion, it is argued that the systematic significance of Helmholtz's empirico-transcendentalism with respect to questions of the mind is best understood as an attempt to found his empirical theory of perception in a second order, normative account of epistemic subjectivity. (shrink)

Depending on different positions in the debate on scientific realism, there are various accounts of the phenomena of physics. For scientific realists like Bogen and Woodward, phenomena are matters of fact in nature, i.e., the effects explained and predicted by physical theories. For empiricists like van Fraassen, the phenomena of physics are the appearances observed or perceived by sensory experience. Constructivists, however, regard the phenomena of physics as artificial structures generated by experimental and mathematical methods. My paper investigates the historical (...) background of these different meanings of phenomenon in the traditions of physics and philosophy. In particular, I discuss Newton’s account of the phenomena and Bohr’s view of quantum phenomena, their relation to the philosophical discussion, and to data and evidence in current particle physics and quantum optics. (shrink)

Broadly stated, naïve realism is the attitude that the form of our outer experiences directly and literally correspond to the structure of the real world underlying these experiences. Naïve realism permeates our everyday thinking about, and ordinary language description of, the macroscopic world. It has undeniable pragmatic justification. However, as Descartes recognized centuries ago, philosophically speaking, naïve realism requires a justification. Physicists, nevertheless, simply assume naïve realism in interpreting the laboratory observations realistically. Thus, physicists do not find the philosophical issues (...) surrounding the problem of naïve realism to be any of relevance to the development of physics per se. The problem of scientific realism is seen to arise in a different context, that of justifying the idea that our best theories in physics pragmatically succeed because its abstract entities provide a true glimpse of the external world under investigation. (shrink)

The observable/unobservable distinction, realistically construed, is a feature which lies at the very heart of van Fraassen’s constructive empiricism. The aim of this paper is to approach it by taking a close look at van Fraassen’s concept of observation. We will argue that if van Fraassen’s most recent writings about “literate experience”, especially his remarks on the status of observation reports and his general a-metaphysical stance, are taken into account, his realistic interpretation of the observable/unobservable distinction paves the road for (...) inconsistency. In particular, we will show that a dilemma emerges to the effect that van Fraassen is forced to accept skeptical consequences blatantly at odds with constructive empiricism and its restatement of the aim of science. We will finally suggest that the only way out for van Fraassen involves giving up his realistic construal of observability and thus taking sides with constructivism. (shrink)

In science, it sometimes occurs that an event is directly observed, and on other occasions that it is not directly observed but one can make the unambiguous inference that it has occurred. Is there any difference concerning the analysis of data arising from these two situations? In this note we show that there is such a difference in one case arising frequently in genetics. The difference derives from the fact that the ability to make the unambiguous inference arises only from (...) a restricted form of data. (shrink)

Scientific knowledge production is currently affected by the dissemination of data on an unprecedented scale. Technologies for the automated production and sharing of vast amounts of data have changed the way in which data are handled and interpreted in several scientific domains, most notably molecular biology and biomedicine. In these fields, the activity of data gathering has become increasingly technology-driven, with machines such as next generation genome sequencers and mass spectrometers generating billions of data points within hours, and with little (...) need for human supervision. Given the relative ease and low costs with which datasets can be produced (that is, once a laboratory has been able to afford .. (shrink)

The present paper claims that M. S. Tswett’s chromatographic adsorption analysis, which today is a ubiquitous and instrumentally sophisticated chemical technique, was either ignored or outright rejected by chemists and botanists in the first three decades of the twentieth century because it did not make sense in terms of accepted chemical theory or practice. Evidence for this claim is culled from consideration of the botanical and chemical context of Tswett’s technique as well as an analysis of the protracted debate over (...) Tswett’s chromatographic analysis of chlorophyll between him and Leon Marchlewski, a noted chlorophyll chemist of the period. In this way, the paper expands and amends what it calls the ‘textbook story’ of the early history of chromatography, examples of which may be found in historical notes in many textbooks of chemical instrumental analysis and numerous short articles in chemistry journals. The paper also provides an accessible introduction to the early history of chromatography for historians of science likely to know little or nothing about it. (shrink)

The 20th century philosophy of science began on a positivistic note. Its focal point was scientific explanation and the hypothetico-deductive (HD) framework of explanation was proposed as the standard of what is meant by “science.” HD framework, its inductive and statistical variants, and other logic-based approaches to modeling scientific explanation were developed long before the dawn of the information age. Since that time, the volume of observational data and power of high performance computing have increased by several orders of magnitude (...) and reshaped the practice and concept of science, and indeed, the philosophy of science. A new observational-inductive (OI) framework for scientific research is emerging due to recent developments in sensors, data systems, computers, and knowledge discovery techniques. We examine the nature of these changes and their impact on the question of what is meant by “science” after discussing five examples of the OI framework, and conclude that the HD and OI frameworks are complementary and synergistic. (shrink)

In this paper, I argue that Constructive Empiricism (CE) is ambiguous between two interpretations: CE as a normative epistemology of science and CE as a descriptive philosophy of science. When they present CE, constructive empiricists write as if CE is supposed to be more than a normative epistemology of science and that it is meant to be responsible to actual scientific practices. However, when they respond to objections, constructive empiricists fall back on a strictly normative interpretation of CE. This ambiguity (...) seems to make CE immune to objections in a rather ad hoc fashion. (shrink)

Scientists use visualisations of different kinds in a variety of ways in their scientific work. In the following article, we will take a closer look at the use of photographic pictures as scientific evidence. In accordance with Patrick Maynard’s thesis, photography will be regarded as a family of technologies serving different purposes in divergent contexts. One of these is its ability to detect certain phenomena. Nonetheless, with regard to the philosophical thesis of theory-ladenness of observation, we encounter certain reservations concerning (...) the status of photography and that of photographic pictures in the process of measurement in science. Accordingly, the aim of this paper is twofold: We will discuss suggested solutions both for the technological and for the psychological part of the problem of theory-ladenness appearing in the context of the use of photography in scientific observations. The essential proposal will be to follow Christian Suhm in his advice to make a distinction between theory-relativity and theory-ladenness. (shrink)

Today we are all familiar with the iconic pictures of the nebulae produced by the Hubble Space Telescope’s digital cameras. But there was a time, before the successful application of photography to the heavens, in which scientists had to rely on handmade drawings of these mysterious phenomena. Observing by Hand sheds entirely new light on the ways in which the production and reception of handdrawn images of the nebulae in the nineteenth century contributed to astronomical observation. Omar W. Nasim investigates (...) hundreds of unpublished observing books and paper records from six nineteenth-century observers of the nebulae: Sir John Herschel; William Parsons, the third Earl of Rosse; William Lassell; Ebenezer Porter Mason; Ernst Wilhelm Leberecht Tempel; and George Phillips Bond. Nasim focuses on the ways in which these observers created and employed their drawings in data-driven procedures, from their choices of artistic materials and techniques to their practices and scientific observation. He examines the ways in which the act of drawing complemented the acts of seeing and knowing, as well as the ways that making pictures was connected to the production of scientific knowledge. An impeccably researched, carefully crafted, and beautifully illustrated piece of historical work, Observing by Hand will delight historians of science, art, and the book, as well as astronomers and philosophers. (shrink)

The chemical characterization of the substance responsible for the phenomenon of “transformation” of pneumococci was presented in the now famous 1944 paper by Avery, MacLeod, and McCarty. Reception of this work was mixed. Although interpreting their results as evidence that deoxyribonucleic acid (DNA) is the molecule responsible for genetic changes was, at the time, controversial, this paper has been retrospectively celebrated as providing such evidence. The mixed and changing assessment of the evidence presented in the paper was due to the (...) work’s interpretive flexibility – the evidence was interpreted in various ways, and such interpretations were justified given the neophytic state of molecular biology and methodological limitations of Avery’s transformation studies. I argue that the changing context in which the evidence presented by Avery’s group was interpreted partly explains the vicissitudes of the assessments of the evidence. Two less compelling explanations of the reception are a myth-making account and an appeal to the wartime historical context of its publication. (shrink)

Let us call ‘veridicalism’ the view that perceptual beliefs and observational reports are largely truthful. This paper aims to make a case for veridicalism by, among other things, examining in detail and ultimately deflating in import what many consider to be the view’s greatest threat, the so-called ‘theory-ladenness’ of perception and/or observation. In what follows, it is argued that to the extent that theoretical factors influence the formation of perceptual beliefs and observational reports, as theory-ladenness demands, that influence is typically (...) not detrimental to their veridicality or at least not irreversibly so. Central to the defence of veridicalism are two principles: that of internal similarities and that of internal dissimilarities. (shrink)

Russo and Williamson (Int Stud Philos Sci 21(2):157–170, 2007) put forward the thesis that, at least in the health sciences, to establish the claim that C is a cause of E, one normally needs evidence of an underlying mechanism linking C and E as well as evidence that C makes a difference to E. This epistemological thesis poses a problem for most current analyses of causality which, in virtue of analysing causality in terms of just one of mechanisms or difference (...) making, cannot account for the need for the other kind of evidence. Weber (Int Stud Philos Sci 23(2):277–295, 2009) has suggested to the contrary that Giere’s probabilistic analysis of causality survives this criticism. In this paper, we look in detail at the case of medical imaging technology, which, we argue, supports the thesis of Russo and Williamson, and we respond to Weber’s suggestion, arguing that Giere’s account does not survive the criticism. (shrink)