Does the anti-essentialist consensus in philosophy of biology rest on a mistake?
A long-established consensus in the philosophy of biology holds that essentialism about biological species is incompatible with both evolutionary theory and taxonomic practice.
This anti-essentialist consensus has recently been challenged by Michael Devitt, who insists that it rests on a mistake. According to Devitt, philosophers of biology have failed to recognise the distinction between two quite different questions one can ask about species: the Category question and the Taxon question.
The various “species concepts” found in the biological literature are attempts to answer the former but are silent about the latter, Devitt claims, so do not conflict with essentialism, pace what philosophers of biology believe.
By carefully attending to the logical relation between the Category and Taxon questions, Devitt’s claim that the anti-essentialist consensus rests on a mistake is shown to be untenable.
About Samir Okasha
Okasha is Professor of philosophy of science at the University of Bristol. His book “Evolution and the Levels of Selection” (OUP 2006) was awarded the 2009 Lakatos Prize.
He has been working extensively on connections between evolutionary theory and theories of rationality, as well as a range of central topics in contemporary philosophy of science.
He currently directs the Representing Evolution research project, funded by an ERC Advanced Grant.