Theses - History and Philosophy of Science

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The Logical Structure of Scientific Knowledge-Systems
Vos, Bob
This thesis seeks to assess and develop the use of formal methods in philosophy of science. More specifically, I argue that the particular strand of philosophy of science that concerns itself with the formal structure of scientific knowledge has focused excessively on the structure of scientific theories. In response, I consider the prospects for the formal study of other, supratheoretical aspects of science, culminating in the proposal for a research programme centred around the formal study of, what I shall call, scientific knowledge-systems. This line of argument is laid out over the course of two parts, along with an extended introduction. In my extended introduction, I will situate myself with respect to the wider philosophy of science. This is necessary, because the body of work I seek to build on in this thesis is emblematic of a style of philosophy of science, referred to here as the architectonic style, which today has largely fallen out of favour. Accordingly, I will first offer some general arguments for the desirability and viability of this style of metascientific enquiry. In Part I of the thesis, I offer a critical appraisal of extant work on the formal structure of scientific knowledge, referred to there as architectonic metascience. Following an extensive survey of architectonic metascience (Chapter 1), I argue that it suffers from the problem of theory-centrism (Chapter 2). The upshot of this observation, I argue, is that frameworks for the formal study of scientific knowledge should adopt a supra-theoretical unit of analysis (or macro-unit, for short). I conclude my appraisal by discussing the few extant—but seldom acknowledged—examples of the formal study of macro-units (Chapter 3). Finally, in Part II, I seek to make a contribution to the formal study of macro-units. A recurring theme throughout the history of analytic philosophy is the idea that we may draw on the metatheoretical study of logic to inform the metatheoretical study of science. In line with this tradition, I first survey the movement of logical abstractivism, within which we find various frameworks for the systematic study of different systems of logic (Chapter 4). Following this is an intermezzo which presents an existing application of logical abstractivism to philosophy of science (Chapter 5), and a brief discussion on the explication of target systems in formal analyses of science (Chapter 6). Building on these reflections, I set out the programme of metascientific abstractivism for the study of scientific knowledge-systems (Chapter 7).
Open Access
A history of Ohm's Law: Investigating the flow of electrical ideas through the instruments of their production
Connelly, Charlotte; Connelly, Charlotte [0000-0001-9350-044X]
This thesis takes a deep dive into the electrical work of Georg Simon Ohm. It is tightly focused on the period 1825-1827 when he developed and published the famous law we now think of as “Ohm’s law”. This work differs from previous studies of Ohm’s investigations by putting material culture at its heart. Using Ohm’s research as a case study, this project asks: how can the material culture of the physical sciences contribute to contemporary historiography in the history of science? What can we uncover from a material-led investigation that would remain inaccessible in a text-led investigation? And, in this particular case, how does looking closely at Ohm’s experimental apparatus and practice help us to understand the development of his law? As part of the material-led study, this project incorporates a reconstruction and reworking of Ohm’s 1826 experimental apparatus. As something of an outsider, Ohm has defied ready categorisation by historians. This project looks at why that might be, and what his theoretical and methodological influences were. Looking at the way Ohm’s instrument was designed and used, we can see the influence of natural philosophers including Coulomb, Ørsted, Seebeck, Ampère and others, while looking at Ohm’s mathematical treatise reveals the strong influence of Fourier. Perhaps most notable from Ohm’s work in this period is how readily he changed his conceptual approach. Over the course of three years, three distinct phases of work can be identified: in the first phase Ohm used a voltaic, or hydroelectric, pile and described his observations in terms of “loss of force”; in the second he replaced the unstable voltaic pile with a thermocouple and described his observations in terms of “exciting force”; and in the third he set aside his experimental work and focused instead on making mathematical arguments, shifting his language again to describe what was happening in an electrical circuit in terms of “electroscopic force”. The shift between Ohm’s first two phases of work can, this project argues, be made sense of by understanding changes in Ohm’s experimental setup and the way they affected his interaction with the phenomena he was studying. This thesis presents objects and instruments as integrated parts of the thought process of an experimenter, in which the apparatus shapes the thinking of the experimenter as much as the experimenter’s thoughts shape the design of the apparatus. This framework is then applied to Ohm’s work as a case study, leading to the suggestion that Ohm’s material interactions with his experiment shaped his conceptualisation of what was happening in an electrical circuit. It is possible to draw clear links between the conceptual tools and the material tools that Ohm used in his different phases of work; and, in understanding the practical experience Ohm had of using his apparatus, to make sense of his shifting use of language as he moved through different phases of work. Through its material-led approach, this project brings together history, philosophy and material culture of science in a single case study. It presents novel findings about Ohm’s work, uncovered through material engagement with his experimental setup, and offers a set of tools for material-led studies in the history of science.
Controlled Access
Using mathematics in physics: A pragmatic approach
Tomczyk, Hannah
In this thesis, I address the philosophical problem of why mathematics is useful for physics. I discuss the contemporary philosophical debate on the topic, which is focused on the representational role of mathematics. In contrast to this, I then defend a pragmatic view in which representation is only one of the uses of mathematics in physics, and which stresses the use of mathematics in experimental and technological contexts. I argue that physicists can make mathematics useful in concrete situations because they have a language that enables them to coordinate activities in mathematical and concrete contexts. In particular, there are concepts that are meaningful in both contexts of work. I call these “hybrid” concepts, and I analyse them with a view that takes the meaning of a term to be determined by its use. For physicists to successfully combine work in mathematical and concrete contexts, they need to have mastered the accepted uses of hybrid terms in both contexts. In the historical development of science, many concepts underwent changes so that today, they are particularly apt to connect the two contexts of work. I will use two case studies to show how this approach can illuminate the usefulness of mathematics in concrete situations: the development of the concept of “velocity” from its mathematisation in the Middle Ages to its first technological usefulness in the context of gunnery in the eighteenth century, and the development of the term “spin” from its introduction into atomic physics in the 1920s to its use in modern MRI. I claim that if we trace the historical development of hybrid terms with a use-focused view of meaning, it becomes clear why mathematics became more and more useful in experimental and technological contexts.
Open Access
Colour and Colour Vision in Late Nineteenth Century British Sciences
Bridgman, Gregory
This thesis employs a close reading of archival and published sources to explore the origins of colour vision science in 19th century Britain. By drawing attention to wide ranging dialogues and disagreements between diverse figures with different visions of colour, including physicists David Brewster, James Clerk Maxwell, and Lord Rayleigh, politician and philologist William Gladstone, ophthalmologists Frederick Edridge-Green and Robert Carter, and anthropologist W.H.R Rivers, I show that 19th century colour vision science was not narrowly confined to the quantification, measurement, and classification of colours. It was instead shaped by deeper metaphysical questions and wider political concerns. These questions and concerns included the implications of natural law, free-will, and materialism for scientific understandings of reality, the limits of Darwinian understandings of humanity, the legitimacy of scientific experts and institutions in determining public policy, and the history, future, and advancement of civilization. I argue that the widespread use of spinning discs as an experimental research technology, promoted by Brewster and Maxwell, combined with the mainstream acceptance of Maxwell’s theoretical model of ‘coterminal response curves’, generated conflicts between competing understandings of perception, vision, and colour in the second half of the 19th century. These conflicts stemmed from the establishment of new conventions, inspired by Maxwell’s work, which held that scientists should maintain a practical and analytical distance from their own visual experiences, that the visual experiences of test subjects should be treated as untrustworthy phenomena in need of further analysis, and that the meaning of subjective experiences are contained within, and revealed by, mathematical models that accord with a rational understanding of the physical world. These practical and metaphysical approaches to the meaning of human experience did not end with the conflicts they generated in the second half of the 19th century but continue to bear on broader contemporary understandings of truth and illusion in scientific practice and popular imagination.
Open Access
Bridging the gap between populations and individuals in the philosophy of medicine
Scholl, Raphael
The thesis addresses the relationship between populations and individuals in the philosophy of medicine. There is a long-standing tension in the fact that randomised, controlled trials in clinical populations count among the best evidence in medicine, while the goal of medical practice is to help individual patients who may differ from population averages. To what extent is evidence from populations a sufficient guide to the treatment of individuals, and how can it perhaps be improved upon? The thesis consists of five chapters that consider this problem from several complementary perspectives. The first chapter returns to the origins of population studies in medicine: The 1835 debate on medical statistics at the Académie Royale de Médecine in Paris. It argues that the existing literature has neglected core epistemological arguments on which the debate turned, and which made population studies a much more challenging methodological development than we today appreciate. The second chapter moves to a present-day version of the debate. It asks whether physicians ought more frequently to conduct so-called n-of-1 or single-case trials with individual patients. The conclusion is that while such studies are epistemologically sound, they are less useful than they may appear at first glance. The third chapter focuses on so-called molecular network reconstruction, a type of mechanistic discovery strategy that leverages large datasets. While it is often difficult to find strong associations between genetic variants and individual health outcomes, this literature suggests that a higher level of organisation -- the state of entire molecular networks -- can often be associated with individual outcomes. The fourth chapter presents an extended case study of periodontal disease, a common affliction that is well understood in some respects but also presents inter-individual heterogeneity that has been recalcitrant to explanation for decades. The puzzles of the case study lead into the fifth and final chapter, which locates the search for inter-individual variation in disease susceptibility and therapy response in an evolutionary context. It argues that evolutionary models of ultimate disease causation can serve as a heuristic tool for the study of the proximate causes of variation in health outcomes.
Open Access
Experts & AI systems, explanation & trust: A comparative investigation into the formation of epistemically justified belief in expert testimony and in the outputs of AI-enabled expert systems
Seger, Elizabeth; Seger, Elizabeth [0000-0001-8942-4130]
The relationship between human experts and those that seek their advice (novices), and between AI-enabled expert systems and users, are epistemically imbalanced relationships. An epistemically imbalanced relationship is one in which the information source (expert/AI) occupies an epistemically privileged position relative to the novice/user; she/it can utilize capacities, resources, and reasoning techniques to draw conclusions that the novice/user would be unable to access, reproduce, or in some cases, comprehend on her own. The interesting and problematic thing about epistemically imbalanced relationships is that when the epistemically disadvantaged party seeks out expert/AI aid, then in virtue of the novice’s epistemically disadvantaged position, she is not well-equipped to independently confirm the expert/AI’s response. Consider for example, a physician who outlines a cancer treatment regime to a patient. If the physician were then to try to explain to the patient how she decided on that specific regime (including drug doses, timings, etc.) it is not clear how the explanation would help the patient justify her belief in the physician’s claims. If an expert outlines her reasoning in such detail that it provides strong evidence in support of her claim – for instance, such that a series of true premises logically leads to a conclusion – then the novice is unlikely to have the expertise necessary to recognize the evidence as supporting the claim. Accordingly, the question stands, how can the novice, while remaining a novice, acquire justification for her belief in an expert claim? A similar question can be asked of user-AI interactions: How can an AI user, without becoming an expert in the domain in which the AI system is applied, justify her belief in AI outputs? If an answer can be provided in the expert-novice case, then it would seem that we are at least on our way to acquiring an answer for the AI-user case. This dissertation serves a dual purpose as it responds to the above questions. The primary purpose is as an investigation into how AI users can acquire a degree of justification for their belief in AI outputs. I pursue this objective by using the epistemically imbalanced novice-expert relationship as a model to help identify key challenges to user appraisal of AI systems. In so doing, the primary objective is achieved while pursuing the dissertation’s secondary purpose of addressing standing questions about the justification of novice belief in human expert claims. The discussions that follow are framed against an overarching conceptual concern about preserving epistemic security in technologically advanced societies. As my colleagues and I have defined it (Seger et al., 2020), an epistemically secure society is one in which information recipients can reliably identify true information or epistemically trustworthy information sources (human or technological). An investigation into how novices and users might make epistemically well-informed decisions about believing experts and AI systems is therefore an investigation into how we might address challenges to epistemic security posed by epistemically imbalanced relationships.
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Why we need to talk about preferences: A federalist proposal
Beck, Lukas
This doctoral thesis argues that, contrary to the appearances of unity, economists are highly disunified in their understanding of central concepts of choice- and game theory, namely, preferences and beliefs. Even though 'preference' is arguably the most central concept in economics and the discipline is very explicit about the structural assumptions that preferences are supposed to satisfy, there is neither an explicit definition of the concept in economic textbooks nor much of a current debate in the discipline. Nevertheless, the last few years have seen the emergence of several views by philosophers of economics concerning what preferences in economics really are (e.g., judgmentalism, various strands of revealed preferences theory). Trying to defend one such story is, in my view, a mistake. Instead, I propose that we should acknowledge that there is significant disunity about concepts like preferences and beliefs in economics, and that explicating this disunity cannot only help us account for important controversies at the forefront of economic research, but also point us towards potential resolutions. As a first step towards my aim, I demonstrate that the various grand narratives about ‘what preferences in economics really are’ fail to account for substantial contributions and practices in economics. I then argue that this is to be expected as only a minimal conception of preferences holds the federation of economics together. This minimal conception is usually enriched with further implicit assumptions that differ across various research programs and are tailored to the specific agendas of the research programs in which they are employed. One of my central claims is that explicating and appraising these more local assumptions will — in contrast to how the debate currently proceeds — allow philosophers of science to contribute substantially to the progress of economics. The thesis supports this claim by looking in detail at i) the disagreements concerning what kind of experiments microeconomics needs and ii) the recent controversy about preference purification in behavioral welfare economics. Concerning the first debate, I argue that proponents of the heuristics-and-bias program usually put internalist restrictions on the constituents of preferences, while proponents of experimental economics in the tradition of Vernon Smith permit agents' environments to play a crucial role in the constitution of their preferences. Regarding the second debate, I argue that disentangling different substantial notions of rationality, which go beyond its technical meaning in economics, can help us account for the vastly different assessments of the plausibility of preference purification in behavioral welfare economics. Turning back to the big picture, my discussion of i) and ii) highlights that economics has more to gain from an explication of the implicit assumptions about choice- and game-theoretic concepts made by different research programs than from overreaching narratives about ‘what preferences really are.’
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The Prospects of Personalising Medicine
Mncube, Zinhle
Personalised Medicine (PM) is touted as a medical revolution where medical treatment and diagnosis is tailored to the individual patient so that it is optimal, safe, and exactly appropriate. Each chapter in this dissertation deals with the conceptual, methodological, epistemic, or ethical issues of personalising medicine that influence our ability to reliably predict, diagnose, and treat disease for individual patients. I argue that PM in its current form is insufficient in several ways. My dissertation contributes to the literature by providing arguments for why and how we should reconceive of PM. In Chapter 1, I describe and analyse two conceptions of PM: broad-based and biological. I reject the popular claim that biological conceptions of PM are not truly personalised because they do not capture holistic aspects of personhood. Instead, I argue that the real problem for genome-based conceptions is that genomics is frequently imprecise and explanatorily not robust about underlying causes of disease. In Chapter 2, I illustrate that some theorists combine their defence of the use of race in medicine with an appeal to the value-free ideal. Against this view, I contend that contextual value judgements are important in assessing the use of race in medicine because evidence on the epistemic usefulness of racial categories in medicine can be transiently underdetermined and inductively risky. In Chapter 3, I interrogate the controversial use of racial categories in equations to predict kidney function and show that equations that include race in their estimations are inadequate at accurately predicting kidney function. In Chapter 4, I assess the underexplored reliability of what I call the ‘stratification strategy’. This strategy requires that clinicians make therapeutic predictions about individual patients based on evidence of commonly shared molecular biomarker status among patient subgroups. I argue that in many instances of its use, this strategy has low reliability because biomarker evidence lacks credibility. Lastly, in Chapter 5, I draw attention to African Traditional Medicine as a broad-based form of PM. I consider the rationale to decolonise medicine as it applies to African Traditional Medicine in South Africa. I argue that interpreting this rationale as many do—that African Traditional Medicine is epistemically equivalent to Western mainstream medicine—implies an untenable wholesale medical relativism.
Open Access
Gauging a State: Excise Taxation, Practical Mathematics, and Cask Measuring in Seventeenth Century England
Sechrist, Guy
This thesis investigates the mathematical developments and the continued use of gauging instruments designed to calculate the contents of wooden barrels for the purposes of collecting excise revenue for the English state. This research situates the work of mathematical practitioners alongside the practices of excise officers, or gaugers, to examine how the calculation of the contents of barrels became a fundamental part of the English state’s financial development throughout the seventeenth century. By championing the ubiquity of wooden barrels, their examination within the context of England’s financial developments will provide remarkable insight into the connections underpinning the practical advancements that were made in the mathematical sciences, commercial activities, and state knowledge of the brewing trade and excise system. While the thesis argues that the theoretical knowledge of mathematics served to influence and develop the very practical methods excise officers used to gauge barrels, it was ultimately the state’s interest in taxation, via the ability to gauge said barrels, which ultimately drove efforts to develop and refine such practices throughout the century. Previous scholarship on the history of excise generally begins with the Excise Ordinance of 1643. The first three chapters of this thesis are case studies which trace the origins of barrel gauging in relation to the development of early mathematics, and the expanding brewing and wine trade prior to 1643. This research is necessary to highlight the steps that were needed before the English state could enact such an ordinance in the first place.
Open Access
Framed and Framing Inquiry: Development and Defence of John Dewey's Theory of Knowledge
Henne, Celine
This thesis develops Dewey’s theory of inquiry and provides a novel perspective on what realists consider to be Dewey’s most controversial claims: his rejection of the view that inquiry aims at providing an accurate representation of reality, his claim that the object of knowledge is constructed, and his definition of truth in terms of warranted assertibility or fulfilment of the requirements of a problem. My strategy is to draw a gradual and relative distinction between what I call “framed” and “framing” inquiry. While the distinction is not explicitly present in Dewey’s works, it rests on Dewey’s functional distinction between existential and universal propositions. In a framed inquiry, the problem is covered by an existing conceptual framework, which is used to resolve the problem, without being revised. In a framing inquiry, the problem is underdetermined by existing conceptual frameworks, which are created, revised, or expanded. My general argument is that Dewey’s main contribution and controversial claims should be understood in the context of framing inquiry. In Chapter 1, I set the stage for the thesis. I paint the portrait of Dewey as the archetypal anti-realist; I present pragmatism as moving above this debate; and I present the specifically Deweyan brand of pragmatism. In Chapter 2, I introduce the distinction between framed and framing inquiry. In Chapter 3, I argue that realist notions of knowledge as representation, existence as independent facts, truth as correspondence can be cast in terms of framed inquiry, while most realists mistakenly interpret these notions as “unframed.” In the next three chapters, I defend and develop Dewey’s views for framing inquiry. In Chapter 4, I argue that framing inquiry should be construed as articulating rather than representing reality. In Chapter 5, I maintain that Dewey’s view avoids idealism. In Chapter 6, I defend the pragmatist theory of truth as a standard for framing inquiry, by contrast with representational standards.
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Merlin, the Brain, and the Market: Intelligent Machines and Global Order in Public Debates in Britain 1945-50
Rees, Peter
During and immediately after World War Two (1939-1945), influential public debates in Britain concerned the postwar settlement. This was a global war and Britain was a global empire in its final epoch. A crucial aspect of several schemes for reconstruction and the establishment of global order concerned the place of science—an ostensibly global knowledge form—in the social order. Historians have tended to draw on a relatively narrow range of interlocutors to interpret this polemical landscape as a debate over freedom and planning. This thesis offers a new account of this set of influential polemical interactions by examining a richer cast of participants and by attending to the reflexive quality of the media technologies they used to articulate their arguments. I focus on the programmes forged by three major public intellectuals: J D Bernal, C S Lewis, and F A Hayek. These figures are rarely considered in direct relation to one another and are identified with very different intellectual contributions and political positions, but I show how they were each intensely concerned with the nature and role of science in the social order. All three articulated an image of science as a self-organising system of intelligence which would form the basis of global order. Setting these three figures in their social and intellectual milieux, I compare and contrast how Bernal, Lewis, and Hayek articulated their different notions of the global and images of the intelligent machinery which would secure global order. These images included Bernal's technoscientific world brain, Lewis’s fairy-tale protagonist Merlinus Ambrosius, and Hayek’s market or price mechanism. I show how, in each case, the media through which they articulated these images claimed to manifest and exercise the power of the intelligent machinery which they described. These figures’ work to articulate these images in mass media to educate their audiences was the work of forging the new global order. They each attempted to transform readers’ attitudes towards and tacit assumptions about science and the globe and to thereby transform the body politic and reconstitute the relationships between humans, nature, and technology. Often exciting and entertaining, their accounts invited and trained public audiences to participate as actors in a world and to see their enemies as occupying different consciousnesses, times, or worlds. I show how these works were cosmological interventions by examining the rhetorical and iconographical strategies they employed to project the techniques of their own cosmology onto the global history of science. An important output of the thesis is its provision of a historical explanation for why images of science matter in public culture. I argue that these figures deployed images of science to define the criteria for who counted as legitimate experts on human affairs. Finally, I use this analysis to reinterpret significant aspects of the genesis of British sociology of scientific knowledge. My first two chapters focus on Bernal, the third and fourth chapters on Lewis, and my fifth and sixth chapters on Hayek.
Open Access
Why Gauge? Conceptual Aspects of Gauge Theory
Gomes, Henrique
This thesis is about conceptual aspects of gauge theories. Gauge theories lie at the heart of modern physics: in particular, they constitute the standard model of particle physics. At its simplest, the idea of gauge is that nature is best described using a descriptively redundant language; the different descriptions are said to be related by a gauge symmetry. The over-arching question the thesis aims to answer is: how can descriptive redundancy be fruitful for physics? This question embraces many important topics in the philosophical literature on gauge theory, which I will address. This thesis has two main Parts. Part \ref{part:I} provides technical and conceptual background. It relates the redundancies of gauge theories with the redundancies in the foundations of spacetime physics. In particular, to those of Einstein's theory of general relativity, that are more familar to the average philosopher. This Part provides a perspicuous, geometrical understanding of the physics of gauge theory, on a par with the chronogeometric understanding of general relativity. In Part II I will assess two surprising uses of and one contentious question about gauge symmetry. First, I will provide one answer to the question: ``Why gauge theory?'', that is: why introduce redundancies in our models of nature in the first place? This type of answer is pragmatic: because such redundancies are useful for model-building, in a particular way; and they allow us to focus our mathematical apparatus on different aspects of the same phenomena. Second, I present a choice of gauge that is related to a physically natural, and general, splitting of the electric field; which undermines the way one usually thinks of a choice of gauge as motivated by calculational convenience, or as completely arbitrary. Last, I will assess arguments and counter-arguments for the direct physical significance of gauge symmetries. The conclusion provides a second type of answer to the question of ``Why gauge?''. Namely: because we need it to couple subsystems.
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Constructing Science and Status in Charles Darwin’s Cross-Class Correspondence Network
Brassington, Laura Claire
This dissertation uses the letters exchanged between Charles Darwin and individuals of differing socio-economic statuses to examine problems of social definition and intellectual categorisation in science in mid- to late-nineteenth-century Britain. One means by which historians have sought to recover forms of non-elite participation is by examining class specific spaces of knowledge production; by mid- to late-century, however, social and scientific hierarchies were in flux. Through reading and writing, individuals interested in science were able to cross social and geographic distances without ever meeting in person. Darwin exchanged information with a vast array of individuals and communities through correspondence. I examine Darwin’s written exchanges with and about four key figures: Thomas Rivers (1798-1877), a socially-mobile, affluent nurseryman; John Scott (1836-80), a self-taught gardener; George Cupples (1822-91), a genteel writer and dog breeder; and James Croll (1821-90), a janitor-geologist. In line with recent work on the geographies of books and paper documents, I focus on the materiality of letters. I take letters themselves as spatial entities, co-constructed by the sender and recipient, as well as their respective networks. I ask how individuals constructed, managed, and negotiated their status on paper in order to participate in science. I explore how the serial nature of correspondence enabled individuals to build trust through continual exchanges; how letterheadings could productively miscommunicate an author’s status; and how different forms of address could be used to lever an individual into different positions across the social scale. By focusing on the themes of patronage, careers, and the materiality of paper, this thesis contributes to our understanding of social relations in science in a period when the means of communication between individuals and communities were rapidly changing. The changing methods of scientific communications call for us to readdress our understanding of class relations in this period. A new ‘paper landscape’ for science provided opportunities for all social classes to participate in knowledge production, and a space for individuals and communities to collaborate across social and geographical distances. These issues emerge by analysing letters as spaces for cross-class collaboration in science.
Open Access
A Study of the Peripatetic Mechanica
Harris, Arthur
This study aims to understand the aims and methods of a less-studied work from the early Peripatos, the Mechanica. I argue that the Mechanica (Mech.) was an application of natural philosophy to the technical sphere of mechanics. The primary aim is to give causal explanations of various puzzling phenomena in this domain. While the author uses lettered diagrams and specialised, geometrical language to achieve this aim, the arguments should not be described as mathematical or demonstrative. Rather, Mech.’s explanations are fundamentally physical, causal and analogical. In Chapter 1, I describe the structure of Mech., underscoring a degree of coherence across its 35 problems. I provide evidence for dating Mech. to the early Hellenistic period (late 4th – early 3rd c. BCE) and against the attribution to Aristotle. I also take issue with two standard arguments against that attribution: the claim that Mech.’s understanding of natural motion differs from Aristotle’s, and G.E.L. Owen’s claim that Mech. applies the notion of motion and speed at an instant. I then situate Mech. in its intellectual context through a survey of earlier Greek mechanics and mathematical investigations of motion. At the end of the chapter, Note A summarises Mech.’s structure, while Note B examines passages in Aristotle’s certainly authentic works sometimes thought to represent a theory of mechanics. In Chapter 2, I argue that Mech.’s analysis of radial rotation as the combination of two rectilinear motions should be understood as claiming that two motions are present in a rotating radius, rather than as treating the component motions as useful fictions. To show this, I examine Aristotle’s approach to composed motions across several works. I argue that Aristotle’s accounts of change in Physics 3 and 5 imply a distinctive, realist view of component motions, according to which it is a fact that the rotating radius two simultaneous motions rather than a single motion along the same path. I then examine supporting evidence in passages concerning both celestial and sublunary motions. In Chapter 3, I explore two further considerations that arise from Aristotle’s statements on types of locomotion and their compositions. First, I consider how we should understand Aristotle’s division of all motion into straight, circular and mixed. Then I explore the limits of the possible presence of distinct motions in a single object, through examining Aristotle’s claim that no contrary motions can be simultaneously present in a body. In Chapter 4, I undertake a close reading of Mech. problem 1, showing that problem 1’s arguments draw on the resources of geometry to support a basically physical agenda and to deliver a causal explanation. In light of the arguments of Chapters 2-3, I argue that problem 1’s analysis targets radial rotation, which is distinguished from celestial circular motion by the simultaneous presence of two rectilinear motions in the rotating radius. I defend the explanatory potential of Mech.’s causal notion of constraint (ἔκκρουσις) and I explore an unresolved tension between the characterisation of the motions as radial and tangential (849a6-849a19, 852a8-13) and their different representation in a diagram (849a19-849b19). Chapter 5 studies the explanatory strategies of the less-studied problems 4-22, with a focus on their use of lettered diagrams and specialised language. I argue that these problems fundamentally rely on analogies, a kind of reasoning distant from formal geometry, but that they use the specialised language and lettered diagrams of geometry to support these analogies. Since the arguments are analogical rather than deductive, Mech.’s method should not be identified with the demonstrative ideals of Aristotle’s Posterior Analytics. Chapter 6 examines the paradox of Mech. problem 24, known as the Rota Aristotelis. This paradox challenges problem 1’s claims about rotation and thus threatens to overturn Mech.’s explanatory project. I show that the author’s aim is not to provide a geometrical explanation. Rather, he draws two distinct puzzles from the paradoxical phenomenon and answers each of them with a solution based on physical principles. This further substantiates my argument over the previous chapters that Mech. is not so much a mathematical work as an application of natural philosophy to the technical sphere of mechanics. Chapter 7 argues that Physics 7.4’s startling claim that circular and rectilinear motions are incomparable may represent an earlier attempt to solve the Rota Aristotelis paradox. I criticise three alternative explanations of Phys. 7.4’s claim and show how Phys. 7.4’s argument would make sense as a response to the paradox. In Chapter 8, I summarise the arguments of previous chapters.
Open Access
Language on Holiday and the Philosophy of Mind: A Linguistically Sensitive Approach to Phenomenal Consciousness, Pain, and Psychological Predicates
Owesen, Erlend
The aim of this thesis is to contribute to debates about three topics in the philosophy of mind: phenomenal consciousness, pain, and the extension of psychological predicates. Chapter 1 outlines my metaphilosophical views and gives a roadmap to the thesis. Chapter 2 argues that the ‘what-it’s-like’ phrase as it is characteristically used in the literature on phenomenal consciousness has a technical meaning. I argue that this has the consequence that the phrase says nothing informative about phenomenal consciousness and that lay people’s use of the phrase does not show that they believe in phenomenal consciousness. Chapter 3 argues that eliminativism about phenomenal consciousness is a view worth taking seriously. First, I clarify the eliminativist position, then I explain its motivation. Finally, I draw on the discussion in chapter 2 and argue that there is no compelling evidence for lay belief in phenomenal consciousness, hence that we are currently not in a position to say whether common sense counts in favour of eliminativism or realism. Chapter 4 addresses the main problem for eliminativism – the problem of explaining why people believe in phenomenality. I discuss four recently proposed theories and conclude that we are currently not in a position to tell which of these is the most promising eliminativist-friendly explanation of belief in phenomenality, but that the potential of (at least some of) these theories confirms the claim that eliminativism is a view worth taking seriously. Chapter 5 defends the Bodily Theory of pain, according to which pains are bodily occurrences located in an extra-cranial body part, which contrasts with the Experiential Theory, according to which pains are experiences located in the mind or brain. Chapter 6 discusses what a defender of the Bodily Theory should say about the pain-in-mouth argument, i.e. the step from (1) There is a pain in my finger, and (2) My finger is in my mouth, to (3) There is a pain in my mouth. Several accounts have been offered to explain why (1)-(3) sounds wrong. In chapter 6 I offer a novel account – the mereological view – that entails the Bodily Theory of pain. Chapter 7 discusses cognitive scientists’ ascription of psychological predicates to the brain, i.e. when cognitive scientists say things like ‘The brain thinks’. I propose the Synecdoche View, according to which the locutions of cognitive scientists are figurative, with ‘the brain’ referring to the human being, such that ‘The brain thinks’ reports the thinking of the human being, not the thinking of the brain. One consequence of this is that the locutions of cognitive scientists offer no reason to believe that psychological predicates extend to brains. Chapter 8 concludes the thesis by offering a speculative error theory, according to which some of my opponents’ views are based on conceptual conflations.
Open Access
Natural Selection Reconsidered
Shiels, Reuben
In this thesis, I inspect some key assumptions which tend to underpin mainstream accounts of natural selection, noting where those assumptions break down and taking this as a basis for fresh analysis. First, I examine the assumption that natural selection inherently involves struggle or competition. I show selection can take place without zero-sum competition and that competition is not essential for selection to positively facilitate novel adaptations. Moving on to fitness, I address the assumption that biological fitness should be measured as a function of the number of elements of some set of entities (offspring, gene copies or otherwise). Noting cases where selection seemingly acts in terms of persistence and somatic growth, and with these alternative fitness metrics not reducible to one another, I suggest a pluralist stance. Subsequently extending this rationale to the temporal dimension, I show that attempting to measure fitness over any single time frame often fails to capture the action of selection. In later chapters, I explore the possibility of uniting my multiple fitness metrics via a single “common currency” metric. I rule out metrics based around resource or energy consumption, as per Van Valen and others, as unworkable. However, I find some potential in conceptualising the various aspects of fitness in terms of negative entropy. This fails to deliver a quantifiable common currency metric, but does address conceptual issues and allows for the unification of our account of biological fitness with the popular thermodynamic definition of life. The need to buttress earlier arguments necessitates a concluding analysis of the Darwinian population concept. Contra complacent assumptions that they are readily defined, I find that there are no clear means to bound Darwinian populations in many cases. I also argue that analysis of the Darwinian population concept has been confounded by the conflation of pragmatic groupings, assembled for comparative inference, with causally bound Darwinian populations.
Open Access
Mixed Signals: Communication with the Alien in Cold War Radio Astronomy
(2022-02-26) Charbonneau, Rebecca
This dissertation examines the development of radio astronomy and the search for and communication with extraterrestrial intelligence (CETI) from the 1950s through to the early 1980s, with the aim of understanding how these fields reflected the tensions, successes, and anxieties of Cold War science. In the mid-20th century, some radio astronomers in the US and USSR believed CETI would bring about global unity by reminding humans we are one species in a vast, possibly populated cosmos. Using a combination of oral history and archival research, this dissertation demonstrates that the belief in CETI’s peace making possibilities encouraged scientific internationalism, helped spark anti-nuclear activist movements, prompted successful scientific exchanges between nations locked in the Cold War, and contributed to the development of breakthrough scientific techniques still utilized today. Radio astronomy infrastructures also enabled those successes; the tools and techniques utilized by radio astronomers required the use of telescopes scattered around the world, demanding global cooperation and communication to achieve the best possible scientific results. Yet radio astronomy and CETI also benefited from the military and imperialism. The technical requirements of radio telescopes necessitated the construction of government-funded facilities in remote places, and developing remote sites nearly always required dealing with vulnerable populations and, often, colonized land. Therefore, while US and Soviet astronomers were preoccupied with fighting political barriers that impeded their freedom to conduct scientific research, they were simultaneously treading upon the rights and desires of the communities where their instruments were deployed. Furthermore, CETI radio astronomers became adept at developing tools and techniques to identify intelligent extraterrestrial signals from space. That focus made the field significant for the intelligence community, which used CETI’s signals-intelligence techniques to improve space listening capabilities. This dissertation ultimately argues that radio astronomy and CETI are particularly valuable disciplines through which to analyse many of the major characteristics of Cold War science and geopolitics, because their infrastructure, instruments, and ideologies reveal the dualities and contradictions of the era by promoting communication and internationalism while simultaneously depending on the military, espionage, and imperial hegemony
Controlled Access
The event horizon as a vanishing point: A history of the first image of a black hole shadow from observation
(2021-07-23) Skulberg, Emilie
In 2019, the Event Horizon Telescope Collaboration (EHTC) released the first image of the shadow of a black hole based on observation. This is the closest astronomers have come to imaging a celestial object from which no light can escape. This dissertation offers an account of its formation and early reception based on historical analysis of black hole images published since 1973 in addition to fieldwork and interviews performed at institutions where members of the EHTC work in Harvard and Radboud University. A study of the research techniques and iconography built up over several decades demonstrates that earlier research played a significant role in both the production of [the image], reflected in visual and argumentative strategies deployed by EHTC scientists, and its reception amongst scientists and a broader public. First focusing on points of views in black hole imaging, I show how the framing of the observer in General Relativity took the role of a ‘photographer’ of black holes, and then changed as it was believed that observation from Earth could be possible if using multiple telescopes across the globe. Examining the portrayal of spatial depth in these representations, I trace several ways in which perspective techniques were employed to make spaces close to black holes intuitive to researchers and other audiences, identifying when scientists used approaches which did not rely on forms of perspective familiar from art history. I then focus on the roles spatial relations played in the social and epistemic aspects of the production of images within the EHTC. Finally, I analyse the reception of [the image] with a focus on how the existing iconography of black holes influenced the ways various audiences perceived and reframed the first image from observation.
Open Access
Predicting the Effectiveness of Medical Interventions
Erasmus, Adrian
This dissertation explores several conceptual and methodological features of medical science that influence our ability to accurately predict medical effectiveness. Making reliable predictions about the effectiveness of medical treatments is crucial to mitigating death and disease and improving individual and population health, yet generating such predictions is fraught with difficulties. Each chapter deals with a unique challenge to predictions of medical effectiveness. In Chapter 1, I describe and analyze the principles underlying three prominent approaches to physical disease classification—the etiological, symptom-based, and pathophysiological models—and suggest a broadly pragmatic approach whereby appropriate classifications depend on the goal in question. In line with this, I argue that particular features of the pathophysiological model, such as its focus on disease mechanisms, make it most relevant for predicting medical effectiveness. Chapter 2 explores the debate between those who argue that statistical evidence is sufficient for inferring medical effectiveness and those who argue that we require both statistical and mechanistic evidence. I focus on the question of how mechanistic and statistical evidence can be integrated. I highlight some of the challenges facing formal techniques, such as Bayesian networks, and use Toulmin’s model of argumentation to offer a complementary model of evidence amalgamation, which allows for the systematic integration of statistical and mechanistic evidence. In Chapter 3, I focus on p-hacking, an application of analytic techniques that may lead to exaggerated experimental results. I use philosophical tools from decision theory to illustrate how severe the effects of p-hacking can be. While it is typically considered epistemically questionable and practically harmful, I appeal to the argument from inductive risk to defend the view that there are some contexts in which p-hacking may be warranted. Chapter 4 draws attention to a particular set of biases plaguing medical research: Meta-biases. I argue that biases of this type, such as publication bias and sponsorship bias, lead to exaggerated clinical trial results. I then offer a framework, the bias dynamics model, that corrects for the influence of meta-biases on estimations of medical effectiveness. In Chapter 5, I argue against the prominent view that AI models are not explainable by showing how four familiar accounts of scientific explanation can be applied to neural networks. The confusion about explaining AI models is due to the conflation of ‘explainability’, ‘understandability’, and ‘interpretability’. To remedy this, I offer a novel account of AI-interpretability, according to which an interpretation is something one does to an explanation with the explicit aim of producing another, more understandable, explanation.
Open Access
The Machine–Organism Distinction
Brunet, Tyler; Brunet, Tyler [0000-0002-7609-7254]
The idea that analysis of organisms can proceed by distinguishing organisms from machines is common to many areas of philosophy. This thesis argues that our search for a philosophy of organisms should not proceed by defining or relying on a Machine–Organism Distinction (MOD). We are often able to take biological theories that are thought to characterize organ- isms, such as theories of organismal autonomy and stability, and apply them to machines. I argue that we should not provide an analysis of organisms according to an MOD because there is no distinction available that holds up to scrutiny and evidence. There have been several major attempts to provide an MOD. I divide these in consecutive chapters according to the property of organisms offered as an MOD: teleology (Nicholson 2013), autonomy (Mossio and Moreno 2015), stochasticity (Skillings 2015; Godfrey-Smith 2016) and pro- cessual stability (Dupré and Nicholson 2018). I address these major attempts to provide an MOD by showing how each fails to provide an analysis of organisms that distinguishes them from machines. To do this, I examine a diversity of machines and organisms that serve as naturalistic counterexamples. Discoveries in molecular biology and ecology, as well as developments in robotics and biotechnology, show the failure of MODs in contemporary philosophy and biology. Moreover, not only does the MOD consistently fail, but philosophical arguments that rely upon MODs consistently misrepresent organisms themselves. I conclude with the idea that we should consider machines not as external to, or distinguished from, organisms, but as proper objects of biological science.