Harald A. Wiltsche

This volume brings together philosophers and physicists to explore the parallels between Quantum Bayesianism, or QBism, and the phenomenological tradition. It is the first book exclusively devoted to phenomenology and quantum mechanics. By emphasizing the role of the subject's experiences and expectations, and by explicitly rejecting the idea that the notion of physical reality could ever be reduced to a purely third-personal perspective, QBism exhibits several interesting parallels with phenomenology. The central message of QBism is that quantum probabilities must be interpreted as the experiencing agent's personal Bayesian degrees of belief--degrees of belief for the consequences of their actions on a quantum system. The chapters in this volume elaborate whether and specify how phenomenology could serve as the philosophical foundation of QBism. This objective is pursued from the perspective of QBists engaging with phenomenology as well as the perspective of phenomenologists engaging with QBism. These approaches enable us to realize a better understanding of quantum mechanics and the world we live in, achieve a better understanding of QBsim, and introduce the phenomenological foundations of quantum mechanics. Phenomenology and QBism is an essential resource for researchers and graduate students working in philosophy of physics, philosophy of science, quantum mechanics, and phenomenology.

The aim of this paper is to show that scientific thought experiments and works of science fiction are highly suitable tools for facilitating and increasing understanding of science. After comparing one of Einstein’s most famous thought experiments with the science fiction novel “The Forever War”, I shall argue that both proceed similarly in making some of the more outlandish consequences of special relativity theory intelligible. However, as I will also point out, understanding in thought experiments and understanding in science fiction differ in one important respect: While the former aim at what I shall call “physical understanding”, science fiction novels typically have “existential understanding” as their target.

This book offers fresh perspective on the role of phenomenology in the philosophy of physics which opens new avenues for discussion among physicists, "standard" philosophers of physics and philosophers with phenomenological leanings. Much has been written on the interrelations between philosophy and physics in the late 19th and early 20th century, and on the emergence of philosophy of science as an autonomous philosophical sub-discipline. This book is about the under-explored role of phenomenology in the development and the philosophical interpretation of 20th century physics. Part 1 examines questions about the origins and value of phenomenological approaches to physics. Does the work of classical phenomenologists such as Husserl, Merleau-Ponty or Heidegger contain elements of systematic value to both the practice and our philosophical understanding of physics? How did classical phenomenology influence “standard” philosophy of science in the Anglo-American and other traditions? Part 2 probes questions on the role of phenomenology in the philosophies of physics and science: - Can phenomenology help to solve “Wigner’s puzzle”, the problem of the "unreasonable effectiveness" of mathematics in describing, explaining and predicting empirical phenomena? - Does phenomenology allow better understanding of the principle of gauge invariance at the core of the standard model of contemporary particle physics? - Does the phenomenological notion of “Lifeworld” stand in opposition to the “scientific metaphysics” movement, or is there potential for dialogue? Part 3 examines the measurement problem. Is the solution outlined by Fritz London and Edmond Bauer merely a re-statement of von Neumann’s view, or should it be regarded as a distinctively phenomenological take on the measurement problem? Is phenomenology a serious contender in continuing discussions of foundational questions of quantum mechanics? Can other interpretational frameworks such as quantum Bayesianism benefit from implementing phenomenological notions such as constitution or horizonal intentionality?

As is well known, the late Husserl warned against the dangers of reifying and objectifying the mathematical models that operate at the heart of our physical theories. Although Husserl’s worries were mainly directed at Galilean physics, the first aim of our paper is to show that many of his critical arguments are no less relevant today. By addressing the formalism and current interpretations of quantum theory, we illustrate how topics surrounding the mathematization of nature come to the fore naturally. Our second aim is to consider the program of reconstructing quantum theory, a program that currently enjoys popularity in the field of quantum foundations. We will conclude by arguing that, seen from this vantage point, certain insights delivered by phenomenology and quantum theory regarding perspectivity are remarkably concordant. Our overall hope with this paper is to show that there is much room for mutual learning between phenomenology and modern physics.

The aim of this paper is to present an outline of a phenomenological theory of thought experiments. In doing so, I am dealing with a topic that is currently starting to receive increased attention from philosophers with phenomenological leanings. However, since no serious attempt has been made to tackle the issue in a systematic fashion, I will not merely review existing phenomenological work on thought experiments. For the most part, my paper is programmatic: its aim is to suggest some basic directions in which a phenomenological theory of scientific thought experiments should be developed.

Don Ihde has recently launched a sweeping attack against Husserl’s late philosophy of science. Ihde takes particular exception to Husserl’s portrayal of Galileo and to the results Husserl draws from his understanding of Galilean science. Ihde’s main point is that Husserl paints an overly intellectualistic picture of the “father of modern science”, neglecting Galileo’s engagement with scientific instruments such as, most notably, the telescope. According to Ihde, this omission is not merely a historiographical shortcoming. On Ihde’s view, it is only on the basis of a distorted picture of Galileo that Husserl can “create“ the division between Lifeworld and the “world of science“, a division that is indeed fundamental for Husserl’s overall position. Hence, if successful, Ihde’s argument effectively undermines Husserl’s late philosophy of science. The aim of this paper is to show that Ihde’s criticism does not stand up to closer historical or philosophical scrutiny.

An explorative contribution to the ongoing discussion of thought experiments. While endorsing the majority view that skepticism about thought experiments is not well justified, in what follows we attempt to show that there is a kind of “bodiliness” missing from current accounts of thought experiments. That is, we suggest a phenomenological addition to the literature. First, we contextualize our claim that the importance of the body in thought experiments has been widely underestimated. Then we discuss David Gooding's work, which contains the only explicit recognition of the importance of the body to understanding thought experiments. Finally, we introduce a phenomenological perspective of the body, which will give us the opportunity to sketch the power and promise of a phenomenological approach to thought experiments

Quentin Meillassoux has recently launched a sweeping attack against ‘correlationism’. Correlationism is an umbrella term for any philosophical system that is based on ‘the idea [that] we only ever have access to the correlation between thinking and being, and never to either term considered apart from the other’. Thus construed, Meillassoux' critique is indeed a sweeping one: It comprises major parts of the philosophical tradition since Kant, both in its more continental and in its more analytical outlooks. In light of this critique, the aim of this paper is twofold: On the one hand, I shall defend phenomenology against Meillassoux' main argument, the ‘argument from ancestrality’. On the other hand, I will argue that this argument, albeit unsuccessful in its original form, can be modified to pose a more serious threat. Although this modified version can also be circumvented, it forces phenomenologists to clarify their stance towards the natural sciences.

Husserl holds the view that givenness through adumbrations (i.e. perspectival givenness) is an essential characteristic of the givenness of spatiotemporal things. He goes so far to say that we are dealing with an essential law. In this article I try to make sense of this claim. I am also dealing with a thought experiment that is designed to show that the givenness through adumbrations is just a consequence of our physiological make-up, a view that Husserl explicitly rejects. Amongst other things, I defend Husserl by introducing the crucial distinction between first-person-imagination and third-person-imagination.

The debate about scientific realism has occupied center stage in philosophy of science since its very inception. The main question is whether or not scientific theories are true descriptions of the world. Or, to give the question a slightly different spin: What grounds do we have for believing in the reality of the unobservable entities postulated by contemporary science ? Although the main arena of this debate is analytic philosophy, it is clear that these questions are no less important for philosophers with phenomenological leanings. Should phenomenologists advocate SR or should they opt for scientific anti-realism ? And, on a more historical note, which of these options is most appropriate from the viewpoint of Husserl’s work?Such are the questions that Lee Hardy tries to answer in his book. Hardy’s main thesis is “that Husserl was indeed an instrumentalist, but that his instrumen ..

Abstract Not much scholarly work is needed in order to stumble across many passages where Edmund Husserl seems to advocate an anti-realist attitude towards the natural sciences. This tendency, however, is not well-received within the secondary literature. While some commentators criticize Husserl for his alleged scientific anti-realism, others argue that Husserl's position is much more realist than the first impression indicates. It is against this background that I want to argue for the following theses: a) The basic outlook of Husserl's epistemology as well as his more substantial comments regarding the natural sciences indeed result in a (sophisticated version of) scientific anti-realism which bears certain resemblances to Bas van Fraassen's constructive empiricism; b) This scientific anti-realism can be defended against the two most common objections raised in the secondary literature; c) It is only by means of this sophisticated version of scientific anti-realism that phenomenology can circumvent the problem of ?scientific objectivism?