Ontic structural realists hold that structure is all there is, or at least all there is fundamentally. This thesis has proved to be puzzling: What exactly does it say about the relationship between objects and structures? In this article, I look at different ways of articulating ontic structural realism in terms of the relation between structures and objects. I show that objects cannot be reduced to structure, and argue that ontological dependence cannot be used to establish strong forms of structural (...) realism. At the end, I show how a weaker, but controversial, form of structural realism can be articulated on the basis of ontological dependence. (shrink)

In this paper I aim to answer two questions: Can spin be treated as a determinable? Can a treatment of spin as a determinable be used to understand quantum indeterminacy? In response to the first question I show that the relations among spin number, spin components and spin values cannot be captured by a single determination relation; instead we need to look at spin number and spin value separately. In response to the second question I discuss three ways in which (...) the determinables model might be modified to account for indeterminacy, and argue that none of them is fully successful in helping us to understand quantum indeterminacy. (shrink)

Realists about science tend to hold that our scientific theories aim for the truth, that our successful theories are at least partly true, and that the entities referred to by the theoretical terms of these theories exist. Antirealists about science deny one or more of these claims. A sizable minority of philosophers of science prefers not to take sides: they believe the realism debate to be fundamentally mistaken and seek to abstain from it altogether. In analogy with other realism debates (...) I will call these philosophers quietists. In the philosophy of science quietism often takes a somewhat peculiar form, which I will call naturalistic quietism. In this paper I will characterize Maddy’s Second Philosophy as a form of naturalistic quietism, and show what the costs for making it feasible are. (shrink)

Are laws of nature necessary, and if so, are all laws of nature necessary in the same way? This question has played an important role in recent discussion of laws of nature. I argue that not all laws of nature are necessary in the same way: conservation laws are perhaps to be regarded as metaphysically necessary. This sheds light on both the modal character of conservation laws and the relationship between different varieties of necessity.

Werner Heisenberg's 1925 paper ‘Quantum-theoretical re-interpretation of kinematic and mechanical relations’ marks the beginning of quantum mechanics. Heisenberg famously claims that the paper is based on the idea that the new quantum mechanics should be ‘founded exclusively upon relationships between quantities which in principle are observable’. My paper is an attempt to understand this observability principle, and to see whether its employment is philosophically defensible. Against interpretations of ‘observability’ along empiricist or positivist lines I argue that such readings are philosophically (...) unsatisfying. Moreover, a careful comparison of Heisenberg's reinterpretation of classical kinematics with Einstein's argument against absolute simultaneity reveals that the positivist reading does not fit with Heisenberg's strategy in the paper. Instead the appeal to observability should be understood as a specific criticism of the causal inefficacy of orbital electron motion in Bohr's atomic model. I conclude that the tacit philosophical principle behind Heisenberg's argument is not a positivistic connection between observability and meaning, but the idea that a theory should not contain causally idle wheels. (shrink)

Theories in fundamental physics are unlikely to be ontologically neutral, yet they may nonetheless fail to offer decisive empirical support for or against particular metaphysical positions. I illustrate this point by close examination of a particular objection raised by Wolfgang Pauli against Hermann Weyl. The exchange reveals that both parties to the dispute appeal to broader epistemological principles to defend their preferred metaphysical starting points. I suggest that this should make us hesitant to assume that in deriving metaphysical conclusions from (...) physical theories we place our metaphysical theories on a purely empirical foundation. The metaphysics within a particular physical theory may well be the result of a priori assumptions in the background, not particular empirical findings. (shrink)