Stathis Psillos

This chapter examines the philosophical trajectory of Ramsey sentences from Frank Ramsey’s original discussion in “Theories” to their later deployment by Rudolf Carnap, David Lewis, and contemporary structural realists. It argues that Ramsey sentences have frequently been appropriated in support of broadly antirealist approaches in the philosophy of science—approaches that either deny or paraphrase theoretical commitments to unobservable entities—even though they cannot ultimately sustain such interpretations. We reconstruct Ramsey’s introduction of his existentialized account of theories against the background of the positivist project of eliminating theoretical terms and emphasize the pragmatist motivations underlying his rejection of explicit definitions. We then examine Carnap’s re-invention of Ramsey sentences as part of his attempt to secure a compatibilist position between realism and instrumentalism and argue that Carnap’ strategy ultimately fails. Finally, we discuss later Ramseyan approaches, focusing on structural realism and Lewis’s “Ramseyan Humility,” and contend that they face serious difficulties, at least when intended as moderate realist positions.

Stathis Psillos explores a fundamental ontological puzzle pertaining to powers, in the editors’ opinion perhaps the most fundamental one, namely the internal coherence of their dual nature. On the one hand, powers are intrinsic properties of their objects. They are really and truly predicated of their subjects because they are, strictly speaking, constituents of their subjects. Thus their beings are tied to their objects in a way that makes the rest of the world irrelevant for them, and this way is typically characterized through a counterfactual: even if everything else in the world were different, or if nothing else existed in the world, object X would possess any and all powers Φ that it now possesses in the actual world. But, on the other hand, powers are also directed toward their manifestations. This notion of directed is somewhat vague and difficult to nail down, but at the very least it prima facie implies that powers in some important way depend on something external to them and their object. The implication and its externality are crystal clear in most cases: an active/passive power requires the existence of its co-relative as a necessary condition for that power’s ever being manifested. And insofar as the existence of a power depends on the possibility of its being manifested, the existence of any power Φ now seems to require the existence of its co-relatives and, consequently, the bearers of those co-relatives.

The aim of this chapter is to revisit the major arguments of the seventeenth-century debate concerning laws and powers in service of two main points. First, though the dominant conception of nature was such that there was no room for power in bodies, the very idea that laws govern the behaviour of (bits of) matter in motion brought with it the following issue, which came under sharp focus in the work of Leibniz: _how can passive matter, devoid of power, obey laws?_ Though Leibniz’s answer was to reintroduce powers, two radically different conceptualizations of the relation between laws and powers became available after him. Hume denied powers altogether, whereas Newton thought that to introduce a power is to introduce a law. Second, though laws were meant to replace powers, the real dilemma ended up being not laws vs. powers, but rather necessity vs. non-necessity in nature.

This chapter discusses the problems faced by the two standard theories of reference, namely descriptivist theories of reference and causal theories of reference. It defends causal descriptivism as an alternative account of the reference of the theory-dependent terms. The characterization descriptivist theories are not accidental, since the key ideas have undertaken considerable modifications over the years and in light of important philosophical controversies. Semantic holism contributed significantly to the wide acceptance of the claim that theoretical discourse is meaningful and that theoretical terms have putative factual reference. The chapter argues that a hybrid theory of reference of theoretical terms is independently well-motivated and meets in a satisfactory way conditions of an adequate theory of reference. Finally, it unravels the key difficulties of a recent attempt to dissolve the issue of the reference of theoretical terms by recourse to Ramsey sentences.

This paper advances the thesis of methodological mechanism, the claim that to be committed to mechanism is to adopt a certain methodological postulate, i.e. to look for causal pathways for the phenomena of interest. We argue that methodological mechanism incorporates a minimal account of understanding mechanisms, according to which a mechanism just is a causal pathway described in the language of theory. In order to argue for this position we discuss a central example of a biological mechanism, the mechanism of cell death, known as apoptosis. We argue that this example shows that our philosophically deflationary account is sufficient in order to have an illuminating account of mechanisms as the concept is used in biology.

What is the nature of causation? How is causation linked with explanation? And can there be an adequate theory of explanation? These questions and many others are addressed in this unified and rigorous examination of the philosophical problems surrounding causation, laws and explanation. Part 1 of this book explores Hume's views on causation, theories of singular causation, and counterfactual and mechanistic approaches. Part 2 considers the regularity view of laws and laws as relations among universals, as well as recent alternative approaches to laws. Part 3 examines the issues arising from deductive-nomological explanation, statistical explanation, the explanation of laws and the metaphysics of explanation. Accessible to readers of all levels, this book provides an excellent introduction to one of the most enduring problems of philosophy.

Scientific realism is the optimistic view that modern science is on the right track: that the world really is the way our best scientific theories describe it. In his book, Stathis Psillos gives us a detailed and comprehensive study which restores the intuitive plausibility of scientific realism. We see that throughout the twentieth century, scientific realism has been challenged by philosophical positions from all angles: from reductive empiricism, to instrumentalism and to modern sceptical empiricism. _Scientific Realism_ explains that the history of science does not undermine the arguments for scientific realism, but instead makes it reasonable to accept scientific realism as the best philosophical account of science, its empirical success, its progress and its practice. Anyone wishing to gain a deeper understanding of the state of modern science and why scientific realism is plausible, should read this book.

_The Routledge Companion to Philosophy of Science_ is an indispensable reference source and guide to the major themes, debates, problems and topics in philosophy of science. It contains sixty-two specially commissioned entries by a leading team of international contributors. Organized into four parts it covers: _historical and philosophical context _ _debates _ _concepts _ _the individual sciences._ _The Routledge Companion to Philosophy of Science_ addresses all of the essential topics that students of philosophy of science need to know - from empiricism, explanation and experiment to causation, observation, prediction and more - and contains many helpful features including chapters on individual sciences (such as biology, chemistry, physics and psychology), further reading and cross-referencing at the end of each chapter. Expanded and revised throughout, this second edition includes new chapters on Conventionalism, Social Epistemology, Computer Simulation, Thought Experiments, Pseudoscience, Species and Taxonomy, and Cosmology.

In a recent series of papers, John Worrall has defended and elaborated a philosophical position – traced back to Poincaré– which he calls structural realism. This view stands in between scientific realism and agnostic instrumentalism and intends to accommodate both the intuitions that underwrite the ‘no miracles’ argument for scientific realism and the existence of scientific revolutions which lead to radical theoretical changes. Structural realism presents itself as the best of both worlds. In this paper I critically examine the epistemic status of structural realism, and argue that it is not the best of both worlds. Yet, I stress that it reveals an insight which, properly understood, can cast new light on the debates over scientific realism

When we philosophers think about causation we are primarily interested in what causation is—what exactly is the relation between cause and effect? Or, more or less equivalently, how and in virtue of what is the cause connected to the effect? But we are also interested in an epistemic issue, viz., the possibility of causal knowledge: how, if at all, can causal knowledge be obtained? The two issues are, of course, conceptually distinct—but to many thinkers, there is a connection between them. A metaphysical account of causation would be useless if it did not make, at least in principle, causal knowledge possible. Conversely, many philosophers, mostly of an empiricist persuasion, have taken the possibility of causal knowledge to act as a constraint on the metaphysics of causation: no feature that cannot in principle become the object of knowledge can be attributed to causation

In this paper Venn's account of probability inference and induction is examined, tracing their differences as well as how they ‘co-operate’ in inferences from particulars to particulars. We discuss the role of mathematical idealizations in making probability inferences, the celebrated rule of succession and we delve into the nature of the reference class problem arguing that for Venn it is a common problem for both induction and inference in probability. Our approach is both historical and philosophical attempting to sketch Venn's position both in the philosophy of probability and induction of his time and in relation to the twentieth-century frequentism.

The goal of this paper is to outline and defend an empiricist metaphysics of laws of nature. The key empiricist idea is that there are regularities without regularity-enforcers. Differently put, there are natural laws without law-makers of a distinct metaphysical kind. This outline relies on the concept of a ‘natural pattern’ and more significantly on the existence of a network of natural patterns in nature. The relation between a regularity and a pattern will be analysed in terms of mereology. Here is the road map. In section 2, I briefly discuss the relation between empiricism and metaphysics, aiming to show that an empiricist metaphysics is possible. In section 3, I offer arguments against stronger metaphysical views of laws. Then, in section 4, I motivate nomic objectivism. In section 5, I address the question ‘what is a regularity?’ and develop a novel answer to it, based on the notion of a pattern. In section 6, I analyse the notion of pattern and in section 7 I raise the question: ‘what is a law of nature?’, the answer to which is: a law of nature is a regularity that is characterised by the unity of a natural pattern.El objetivo de este artículo es plantear y defender una metafísica empirista sobre las leyes de la naturaleza. La idea empirista clave es que hay regularidades sin que se requiera la existencia de algo que haga que se mantengan como tales (regularity-enforcers). Dicho de otro modo, hay leyes naturales sin que lo que produce la ley (law-maker) pertenezca a una categoría metafísica diferente. Este plan se apoya en el concepto de “esquema natural” (natural pattern) y en la existencia de una red de esquemas naturales en la naturaleza. La relación entre una regularidad y un esquema se analizará en términos mereológicos. Explico la ruta que seguiré. En la sección 2 discuto brevemente la relación entre empirismo y metafísica con objeto de mostrar que una metafísica empirista es posible. En la sección 3 doy argumentos contra concepciones de las leyes más metafísicas. Después, en la sección 4, apoyo el objetivismo nómico. En la 5 abordo la pregunta ‘¿qué es una regularidad?’ y desarrollo una respuesta novedosa, basada en la noción de esquema. En la sección 6 analizo la noción de esquema y en la 7 planteo la cuestión ‘¿qué es una ley de la naturaleza?’, cuya respuesta es: una ley de la naturaleza es una regularidad que se caracteriza por la unidad de un esquema natural.

Science as Salvation: a Modern Myth and its Meaning, Mary Midgley, 1994. London, Routledge x +256pp., Hb 04 15062713, £35; Pb 04 15107733, £8.99 Philosophical Naturalism, David Papineau, 1993 Oxford, Basil Blackwell xii +219pp., Hb 0631189025, £40; Pb 0631189033, £14.99 F. H. Bradley, Writings on Logic and Metaphysics, James W. Allard & Guy Stock (Eds), 1994. Oxford, Clarendon Press xv+357pp, Hb 0–198–24445–2, £40.00; Pb 0–198–24438‐X, £14.95 Invariance and Heuristics: Essays in Honour of Heinz Post, Steven French & Harmke Kamminga (Eds), 1993 Boston Studies in the Philosophy of Science, Vol. 148 Kluwer Academic Publishers, Dordrecht Beyond Reason: Essays on the Philosophy of Paul Feyerabend, GONZALO MUNÉVAR (Ed.), 1991. Dordrecht, Kluwer Academic Publishers xxi + 535pp., hb, ISBN 0–7923–1272–4, £104.20 World Changes: Thomas Kuhn and the Nature of Science, Paul Horwich (Ed.), 1993. Cambridge, MA, Bradford Books/mit Press vi + 356pp., pb, ISBN 0262581388, £14.95 Realism Rescued: How Scientific Progress is Possible, Jerold L. Aronson, Rom Harré & Eileen Cornell Way, 1994 London, Duckworth vii +213pp., Hb 0715624768, £30.00 Scientific Nihilism: On the Loss and Recovery of Physical Explanation, Daniel Athearn, 1994. State University of New York Press, Albany ix + 387pp., Hb ISBN 0–7914–1807–3, £52 Theism, Atheism, and Big Bang Cosmology, William Lane Craig & Quentin Smith, 1993. Oxford, Clarendon Press x +342pp., Hb 0198263481, £35; Pb 019826383X, £13.95.

Non-Humean accounts of the metaphysics of nature posit either laws or powers in order to account for natural necessity and world-order. We argue that such monistic views face fundamental problems. On the one hand, neo-Aristotelians cannot give unproblematic power-based accounts of the functional laws among quantities offered by physical theories, as well as of the place of conservation laws and symmetries in a lawless ontology; in order to capture these characteristics, commitment to governing laws is indispensable. On the other hand, ontologies that entirely exclude some kind of power ascription to worldly entities (such as primitivism) face what we call the Governing Problem: such ontologies do not have the resources to give an adequate account of how laws play their governing role. We propose a novel dualist model, which, we argue, has the resources to solve the difficulties encountered by its two dominant competitors, without inheriting the problems of either view. According to the dualist model, both laws and powers (suitably conceived) are equally fundamental and irreducible to each other, and both are needed in order to give a satisfactory account of the nomological structure of the world. The dualist model constitutes thus a promising alternative to current monistic views in the metaphysics of science.

What is the nature of causation? How is causation linked with explanation? And can there be an adequate theory of explanation? These questions and many others are addressed in this unified and rigorous examination of the philosophical problems surrounding causation, laws and explanation. Part 1 of this book explores Hume's views on causation, theories of singular causation, and counterfactual and mechanistic approaches. Part 2 considers the regularity view of laws and laws as relations among universals, as well as recent alternative approaches to laws. Part 3 examines the issues arising from deductive-nomological explanation, statistical explanation, the explanation of laws and the metaphysics of explanation. Accessible to readers of all levels, this book provides an excellent introduction to one of the most enduring problems of philosophy.

Scientific realism is the optimistic view that modern science is on the right track: that the world really is the way our best scientific theories describe it. In his book, Stathis Psillos gives us a detailed and comprehensive study which restores the intuitive plausibility of scientific realism. We see that throughout the twentieth century, scientific realism has been challenged by philosophical positions from all angles: from reductive empiricism, to instrumentalism and to modern sceptical empiricism. _Scientific Realism_ explains that the history of science does not undermine the arguments for scientific realism, but instead makes it reasonable to accept scientific realism as the best philosophical account of science, its empirical success, its progress and its practice. Anyone wishing to gain a deeper understanding of the state of modern science and why scientific realism is plausible, should read this book.

This indispensable reference source and guide to the major themes, debates, problems and topics in philosophy of science contains fifty-five specially commissioned entries by a leading team of international contributors. Organized into four parts it covers: historical and philosophical context debates concepts the individual sciences. The _Companion_ covers everything students of philosophy of science need to know - from empiricism, explanation and experiment to causation, observation, prediction and more - and contains many helpful features including: a section on the individual sciences, including chapters on the philosophy of biology, chemistry, physics and psychology, further reading and cross-referencing at the end of each chapter.

In this paper Venn's account of probability inference and induction is examined, tracing their differences as well as how they ‘co-operate’ in inferences from particulars to particulars. We discuss the role of mathematical idealizations in making probability inferences, the celebrated rule of succession and we delve into the nature of the reference class problem arguing that for Venn it is a common problem for both induction and inference in probability. Our approach is both historical and philosophical attempting to sketch Venn's position both in the philosophy of probability and induction of his time and in relation to the twentieth-century frequentism.