James Ladyman

There is good reason to believe that scientific realism requires a commitment to the objective modal structure of the physical world. Causality, equilibrium, laws of nature, and probability all feature prominently in scientific theory and explanation, and each one is a modal notion. If we are committed to the content of our best scientific theories, we must accept the modal nature of the physical world. But what does the scientific realist’s commitment to physical modality require? We consider whether scientific realism is compatible with Humeanism about the laws of nature, and we conclude that it is not. We specifically identify three major problems for the best-systems account of lawhood: its central concept of strength cannot be formulated non-circularly, it cannot offer a satisfactory account of the laws of the special sciences, and it can offer no explanation of the success of inductive inference. In addition, Humeanism fails to be naturalistically motivated. For these reasons, we conclude that the scientific realist must embrace natural necessity.

While there are many examples of metaphysical theorising being heuristically and intellectually important in the progress of scientific knowledge, many people wonder how metaphysics not closely informed and inspired by empirical science could lead to rival or even supplementary knowledge about the world. This paper assesses the merits of a popular defence of the a priori methodology of metaphysics that goes as follows. The first task of the metaphysician, like the scientist, is to construct a hypothesis that accounts for the phenomena in question. It is then argued that among the possible metaphysical theories, the empirical evidence underdetermines the right one, just as the empirical evidence underdetermines the right scientific theory. In the latter case it is widely agreed that we must break the underdetermination by appeal to theoretical virtues, and this is just what should be and largely is done in metaphysics. This is part of a more general line of argument that defends metaphysics on the basis of its alleged continuity with highly theoretical science. In what follows metaphysics and theoretical science are compared in order to see whether the above style of defence of a priori metaphysics is successful.

Whether we think of the routine conviction or acquittal of suspects on the basis of scientific evidence in the law courts, the trust placed in scientific medicine and the extraordinary interventions it makes possible, or the importance that policy makers attach to the opinions of scientists, it is clear that those making up our scientific institutions are among the most authoritative and respected people that there are. Among intellectual endeavours science has an unrivalled dominance in terms of funding, status and influence on practical affairs. However, the days when natural science was widely considered to be a model for the study of the arts and the humanities already seem distant. Indeed the influence of science even within subjects which were conceived of as scientific from their very inception, such as political science and sociology, has waned considerably. Perhaps in economics scientism is still dominant but elsewhere in academia a widespread disillusionment with science has taken hold. Perhaps this is understandable given what were with hindsight the obviously foolish attempts to study everything with the same methodology as is employed in physics. Yet the backlash against a misconceived scientism and reductionism in the study of social life and culture has amounted to more than just a defence of disciplinary boundaries, for critics of science now assail it in its own castles (which they allege are built in the air).

The primacy of physics generates a philosophical problem that the naturalist must solve in order to be entitled to an egalitarian acceptance of the ontological commitments he or she inherits from the special sciences and fundamental physics. The problem is the generalized causal exclusion argument. If there is no genuine causation in the domains of the special sciences but only in fundamental physics then there are grounds for doubting the existence of macroscopic objects and properties, or at least the concreteness of them. The aim of this paper is to show that the causal exclusion problem derives its force from a false dichotomy between Humeanism about causation and a notion of productive or generative causation based on a defunct model of the physical world. †To contact the author, please write to: Department of Philosophy, University of Bristol, 9 Woodland Rd., Bristol BS8 1TB, UK.

According to logical positivism, so the story goes, metaphysical questions are meaningless, since they do not admit of empirical confirmation or refutation. However, the logical positivists did not in fact reject as meaningless all questions about for example, the structure of space and time. Rather, key figures such as Reichenbach and Schlick believed that scientific theories often presupposed a conceptual framework that was not itself empirically testable, but which was required for the theory as a whole to be empirically testable. For example, the theory of Special Relativity relies upon the simultaneity convention introduced by Einstein that assumes that the one-way speed of light is the same in all directions of space. Hence, the logical positivists accepted an a priori component to physical theories. However, they denied that this a priori component is necessarily true. Whereas for Kant, metaphysics is the a priori science of the necessary structure of rational thought about reality , the logical positivists were forced by the history of science to accept that the a priori structure of theories could change. Hence, they defended a notion of what Michael Friedman calls the ‘relativised’ or the ‘constitutive’ a priori. Carnap and Reichenbach held that such an a priori framework was conventional, whereas Schlick seems to have been more of a realist and held that the overall relative simplicity of different theories could count as evidence for their truth, notwithstanding the fact that some parts of them are not directly testable. All this is part of the story of how the verification principle came to be abandoned, and how logical positivism transmuted into logical empiricism

Arguing About Science is an outstanding, engaging introduction to the essential topics in philosophy of science, edited by two leading experts in the field. This exciting and innovative anthology contains a selection of classic and contemporary readings that examine a broad range of issues, from classic problems such as scientific reasoning; causation; and scientific realism, to more recent topics such as science and race; forensic science; and the scientific status of medicine. The editors bring together some of the most influential contributions of famous philosophers in the field, including John Stuart Mill and Karl Popper, as well as more recent extracts from philosophers and scientists such as Ian Hacking, Stephen Jay Gould, Bas van Fraassen, Nancy Cartwright, and John Worrall. The anthology is organised into nine clear sections: science, non science and pseudo-science race, gender and science scientific reasoning scientific explanation laws and causation science and medicine probability and forensic science risk, uncertainty and science policy scientific realism and anti-realism. The articles chosen are clear, interesting, and free from unnecessary jargon. The editors provide lucid introductions to each section in which they provide an overview of the debate, as well as suggestions for further reading.

Few can imagine a world without telephones or televisions; many depend on computers and the Internet as part of daily life. Without scientific theory, these developments would not have been possible. In this exceptionally clear and engaging introduction to philosophy of science, James Ladyman explores the philosophical questions that arise when we reflect on the nature of the scientific method and the knowledge it produces. He discusses whether fundamental philosophical questions about knowledge and reality might be answered by science, and considers in detail the debate between realists and antirealists about the extent of scientific knowledge. Along the way, central topics in philosophy of science, such as the demarcation of science from non-science, induction, confirmation and falsification, the relationship between theory and observation and relativism are all addressed. Important and complex current debates over underdetermination, inference to the best explaination and the implications of radical theory change are clarified and clearly explained for those new to the subject.