This is part of a much larger project on natural kinds and the metaphysics of science. It was presented it at the conference Metaphysics & the Philosophy of Science (May 2011) and published in Biology&Philosophy (Nov 2011).
Homeostatic property clusters (HPCs) are offered as a way of understanding natural kinds, especially biological species. I review the HPC approach and then discuss an objection by Ereshefsky and Matthen, to the effect that an HPC qua cluster seems ill-fitted as a description of a polymorphic species. The standard response by champions of the HPC approach is to say that all members of a polymorphic species have things in common, namely dispositions or conditional properties. I argue that this response fails. Instances of an HPC kind need not all be similar in their exhibited properties. Instead, HPCs should instead be understood as unified by the underlying causal mechanism that maintains them. The causal mechanism can both produce and explain some systematic differences between a kind's members. An HPC kind is best understood not as a single cluster of properties maintained in stasis by causal forces, but as a complex of related property clusters kept in relation by an underlying causal process. This approach requires recognizing that taxonomic systems serve both explanatory and inductive purposes.
@ARTICLE(Magnus2011,
AUTHOR = {P.D. Magnus},
TITLE = {Drakes, seadevils, and similarity fetishism},
JOURNAL = {Biology\&Philosophy},
VOLUME = {26},
NUMBER = {6},
PAGES = {857--870},
MONTH = nov,
YEAR = {2011},
DOI = {10.1007/s10539-011-9284-0}
)
The first on-line draft of this paper was posted 12feb2011.