Major depression (MD) is a highly heterogeneous diagnostic category. Diverse symptoms
such as sad mood, anhedonia, and fatigue are routinely added to an unweighted sum-score …

This essay explores four answers to the question 'What kinds of things are psychiatric
disorders?'Essentialist kinds are classes whose members share an essence from which …

In the modern West, we take for granted that what we call the “natural world” confronts us all
and always has—but Before Nature explores that almost unimaginable time when there was …

The reliance in psychology on verbal definitions means that psychological research is
unusually moored to how humans think and communicate about categories. Psychological …

" Mahoney's starting point is the problem of essentialism in social science. Essentialism--the
belief that the members of a category possess hidden properties (" essences") that make …

The nature of species is controversial in biology and philosophy. Biologists disagree on the
definition of the term 'species,'and philosophers disagree over the ontological status of …

We argue that there are three coherent, nontrivial notions of basic-ness: conceptual basic-
ness, biological basic-ness, and psychological basic-ness. There is considerable evidence …

Philosophers have long been interested in a series of interrelated questions about natural
kinds. What are they? What role do they play in science and metaphysics? How do they …

In Plato's Phaedrus, Socrates is concerned with how things are grouped together and how
they are divided. He makes an analogy with carving up an animal. Just as cuts of meat …

Abstract Richard Boyd's Homeostatic Property Cluster (HPC) Theory is becoming the
received view of natural kinds in the philosophy of science. However, a problem with HPC …