Dimensional quantities such as length, mass and charge, i.e., numbers combined with a conventional unit, are essential components of theories in the sciences. This Element illustrates questions about them by imagining how one would convey the meaning of a kilogram to aliens if one were only allowed to communicate via Morse code.

Christian Pfeiffer explores an important, but neglected topic in Aristotle's theoretical philosophy: the theory of bodies. A body is a three-dimensionally extended and continuous magnitude bounded by surfaces. This notion is distinct from the notion of a perceptible or physical substance. Substances have bodies, that is to say, they are extended, their parts are continuous with each other and they have boundaries, which demarcate them from their surroundings. Pfeiffer argues that body, thus understood, has a pivotal role in Aristotle's natural philosophy. A theory of body is a presupposed in, e.g., Aristotle's account of the infinite, place, or action and passion, because their being bodies explains why things have a location or how they can act upon each other. The notion of body can be ranked among the central concepts for natural science which are discussed in Physics III-IV. The book is the first comprehensive and rigorous account of the features substances have in virtue of being bodies. It provides an analysis of the concept of three-dimensional magnitude and related notions like boundary, extension, contact, continuity, often comparing it to modern conceptions of it. Both the structural features and the ontological status of body is discussed. This makes it significant for scholars working on contemporary metaphysics and mereology because the concept of a material object is intimately tied to its spatial or topological properties.

What are physical quantities, and in particular, what makes them quantitative? This book articulates and defends an original answer to this important, insufficiently understood question through the novel position of substantival structuralism. This position argues that quantitativeness is an irreducible feature of attributes, and quantitative attributes are best understood as substantival structured spaces. The book first explores what it means for an attribute to be quantitative, and what metaphysical implications a commitment to quantitative attributes has. It then sets the stage to address the metaphysical and ontological consequences of the existence of quantitative attributes.

A sophisticated and original introduction to the philosophy of quantum mechanics from one of the world’s leading philosophers of physics In this book, Tim Maudlin, one of the world’s leading philosophers of physics, offers a sophisticated, original introduction to the philosophy of quantum mechanics. The briefest, clearest, and most refined account of his influential approach to the subject, the book will be invaluable to all students of philosophy and physics. Quantum mechanics holds a unique place in the history of physics. It has produced the most accurate predictions of any scientific theory, but, more astonishing, there has never been any agreement about what the theory implies about physical reality. Maudlin argues that the very term “quantum theory” is a misnomer. A proper physical theory should clearly describe what is there and what it does—yet standard textbooks present quantum mechanics as a predictive recipe in search of a physical theory. In contrast, Maudlin explores three proper theories that recover the quantum predictions: the indeterministic wavefunction collapse theory of Ghirardi, Rimini, and Weber; the deterministic particle theory of deBroglie and Bohm; and the conceptually challenging Many Worlds theory of Everett. Each offers a radically different proposal for the nature of physical reality, but Maudlin shows that none of them are what they are generally taken to be.

Quantum theory launched a revolution in physics. But we have yet to understand the revolution's significance for philosophy. Richard Healey opens a path to such understanding. The first part of this book offers a self-contained but opinionated introduction to quantum theory. The second part assesses the theory's philosophical significance.

The nature of matter and the idea of indivisible parts has fascinated philosophers, historians, scientists and physicists from antiquity to the present day. This collection covers the richness of its history, starting with how the Ancient Greeks came to assume the existence of atoms and concluding with contemporary metaphysical debates about structure, time and reality. Focusing on important moments in the history of human thought when the debate about atomism was particularly flourishing and transformative for the scientific and philosophical spirit of the time, this collection covers: - The discovery of atomism in ancient philosophy - Ancient non-Western, Arabic and late Medieval thought - The Renaissance, when along with the re-discovery of ancient thought, atomism became once again an important doctrine to be fully debated - Logical atomism in early analytic philosophy, with Russell and Wittgenstein - Atomism in Liberalism and Marxism - Atomism and the philosophy of time - Atomism in contemporary metaphysics - Atomism and the sciences Featuring 28 chapters by leading and younger scholars, this valuable collection reveals the development of one of philosophy's central doctrines across 2,500 years and within a broad range of philosophical traditions.