Dean Rickles

In this chapter I consider what recent work on background independent physics can do for structuralism, and what structuralism can do for background independent physics. I focus on the problems of time and observables in gravitational physics. The ‘frozen’ character of the observables of general relativity is usually considered to constitute a serious problem for the theory. I argue that by invoking correlations between physical quantities we can provide a natural explanation of the appear- ance of time and change in timeless structures. I argue that this response can resolve a problem with Max Tegmark’s ‘extreme structuralist’ position. I then consider what bearing the mathematical representation used has on the debate over the nature of structure in discussions of structural realism. I argue that it has both the resources to ground the notion of structure in physics and to answer the ‘no relations without relata’ objection.

Structural realism has rapidly gained in popularity in recent years, but it has splintered into many distinct denominations, often underpinned by diverse motivations. There is, no monolithic position known as ‘structural realism,’ but there is a general convergence on the idea that a central role is to be played by relational aspects over object-based aspects of ontology. What becomes of causality in a world without fundamental objects? In this book, the foremost authorities on structural realism attempt to answer this and related questions: ‘what is structure?’ and ‘what is an object?’ Also featured are the most recent advances in structural realism, including the intersection of mathematical structuralism and structural realism, and the latest treatments of laws and modality in the context of structural realism. The book will be of interest to philosophers of science, philosophers of physics, metaphysicians, and those interested in foundational aspects of science.

In this paper I look at causality in the context of intervention research, and discuss some problems faced in the evaluation of causal hypotheses via interventions. I draw attention to a simple problem for evaluations that employ randomized controlled trials. The common alternative to randomized trials, the observational study, is shown to face problems of a similar nature. I then argue that these problems become especially acute in cases where the intervention is complex (i.e. that involves intervening in a complex system). Finally, I consider and reject a possible resolution of the problem involving the simulation of complex interventions. The conclusion I draw from this is that we need to radically reframe the way we think about causal inference in complex intervention research

Stephen Wolfram has recently outlined an unorthodox, multicomputational approach to fundamental theory, encompassing not only physics but also mathematics in a structure he calls The Ruliad, understood to be the entangled limit of all possible computations. In this framework, physical laws arise from the the sampling of the Ruliad by observers (including us). This naturally leads to several conceptual issues, such as what kind of object is the Ruliad? What is the nature of the observers carrying out the sampling, and how do they relate to the Ruliad itself? What is the precise nature of the sampling? This paper provides a philosophical examination of these questions, and other related foundational issues, including the identification of a limitation that must face any attempt to describe or model reality in such a way that the modeller-observers are included.

Why life’s shortness—more than anything else—is what makes it meaningful Death might seem to render pointless all our attempts to create a meaningful life. Doesn’t meaning require transcending death through an afterlife or in some other way? On the contrary, Dean Rickles argues, life without death would be like playing tennis without a net. Only constraints—and death is the ultimate constraint—make our actions meaningful. In Life Is Short, Rickles explains why the finiteness and shortness of life is the essence of its meaning—and how this insight is the key to making the most of the time we do have. Life Is Short explores how death limits our options and forces us to make choices that forge a life and give the world meaning. But people often live in a state of indecision, in a misguided attempt to keep their options open. This provisional way of living—always looking elsewhere, to the future, to other people, to other ways of being, and never committing to what one has or, alternatively, putting in the time and energy to achieve what one wants—is a big mistake, and Life Is Short tells readers how to avoid this trap. By reminding us how extraordinary it is that we have any time to live at all, Life Is Short challenges us to rethink what gives life meaning and how to make the most of it.

During its forty year lifespan, string theory has always had the power to divide, being called both a 'theory of everything' and a 'theory of nothing'. Critics have even questioned whether it qualifies as a scientific theory at all. This book adopts an objective stance, standing back from the question of the truth or falsity of string theory and instead focusing on how it came to be and how it came to occupy its present position in physics. An unexpectedly rich history is revealed, with deep connections to our most well-established physical theories. Fully self-contained and written in a lively fashion, the book will appeal to a wide variety of readers from novice to specialist.

Where does the study of the flow of time belong: physics, the cognitive sciences, philosophy, or somewhere else? Physicists and philosophers have set themselves up into two camps: those who believe there is genuine flow or becoming in the world and those who believe there is just a block of events. What had not been considered is whether the subjective feeling of flow of time is the same the world over, whether it could be tampered with by brain injury, or whether it is present at all developmental stages. We lay out the problem, explain terms, and provide synopses of relevant ideas.

In this essay collection, leading physicists, philosophers, and historians attempt to fill the empty theoretical ground in the foundations of information and address the related question of the limits to our knowledge of the world. Over recent decades, our practical approach to information and its exploitation has radically outpaced our theoretical understanding - to such a degree that reflection on the foundations may seem futile. But it is exactly fields such as quantum information, which are shifting the boundaries of the physically possible, that make a foundational understanding of information increasingly important. One of the recurring themes of the book is the claim by Eddington and Wheeler that information involves interaction and putting agents or observers centre stage. Thus, physical reality, in their view, is shaped by the questions we choose to put to it and is built up from the information residing at its core. This is the root of Wheeler's famous phrase "it from bit." After reading the stimulating essays collected in this volume, readers will be in a good position to decide whether they agree with this view.

This (somewhat polemical) paper focuses on the ontological nature of money and draws comparisons to the ontological status of gauge freedom in physics. The parallels allow us to move beyond the social constructivist theories of Searle et al., and thereby avoid some pitfalls with such views. Since we have a reasonably good grasp of the ontological features in the physics context, we can pull back lessons from there onto the economic domain. In general, we find that this approach offers a nice lens through which to view the ontological peculiarities of money.