I put in question in this article the existence of conjunctive properties. In the second section, after having provided a characterization of conjunctive properties, I develop an argument based on the principle of ontological parsimony: if we accept that there are conjunctive properties in the universe then, ceteris paribus, our ontology turns out to be less ontologically parsimonious than if we reject them. Afterwards, in the third section, I distinguish between maximalist and non-maximalist and reductionist and non-reductionist theories of conjunctive (...) properties., as well as between reductionist and non-reductionist theories that reject conjunctive properties. Such distinctions help to clarify the options at hand when accepting or rejecting conjunctive properties. In light of these distinctions, I then tackle two objections against the argument from ontological parsimony. Finally, in the remaining sections, I deal with two arguments defended by D. M. Armstrong for the existence of conjunctive properties: the argument from infinite complexity and the argument from causal powers. I show that there are several ways to resist these arguments and their conclusion. (shrink)

This paper addresses a famous objection against David Lewis’s Best System Analysis (BSA) of laws of nature. The objection—anticipated and discussed by Lewis (1994)—focuses on the standards of simplicity and strength being (in part) a matter of psychology. Lewis’s answer to the objection relies on his metaphysics of natural properties and its ability to single out the robustly best system, a system that is expected to come out far ahead of its rivals under any standard of simplicity and strength. The (...) main task of this paper is to argue that Lewis’s reply to the objection in terms of nature being kind to us does not succeed, if nature’s kindness is understood in terms of the naturalness of the properties composing the Humean mosaic. For epistemic access to natural properties is downstream to any previous identification of the best system. A possible Lewisian rejoinder in terms of a cross-world Humean mosaic of natural properties is considered and rebutted. The paper concludes by suggesting that Lewis could instead avail himself of a better answer to the objection, if the standards of simplicity and strength were reinterpreted along perspectivalist lines. (shrink)

The identity of a natural kind can be construed in terms of its causal profile. This conception is more appropriate to science than two alternatives. The identity of a natural kind is not determined by one causal role because one natural kind can have many causal roles and several functions and because some functions are shared by different kinds. Furthermore, the microstructuralist thesis is wrong: The identity of certain natural kinds is not determined by their microstructure. It is true that (...) if A and B have the same microstructural composition then a sample of a chemical substance A is of the same chemical substance as a sample of B. However, the reverse does not hold. It is not the case that if a sample of a chemical substance A is of the same chemical substance as a sample of B then A and B have the same microstructural composition. This is because a macroscopic NK can be “multiconstituted” by different microstructures. (shrink)