SAP public lecture (Australia): A Process Theory of Biological Sex, Paul Griffiths (University of Sydney)

SAP public lecture (Australia): A Process Theory of Biological Sex, Paul Griffiths (University of Sydney)


Online event
December 2, 2020 4:00 pm — 6:00 pm

Contact Luara Ferracioli for more information.

[A recording of this event can be viewed here.]

Please note the event will be hosted in Sydney, Australia. 

The event will begin at 4pm Sydney time; 6pm in New Zealand; 6am in London; 10pm in California.


Abstract and Biographical information

Abstract: A Process Theory of Biological Sex

My first thesis is that the statement ‘this species has n sexes’ is properly a statement about a species, a set of populations united in a pattern of ancestry and descent. It is a statement about the role that the number of sexes (n) plays in modelling the evolution of that species. Choosing the right n lets us explain and predict many other features of the species. Each animal species studied to date each uses one or more of three systems for making new individuals: two sexes in discrete individuals, two sexes combined in one individual, and asexual reproduction. So no n greater than 2 has yet been observed. My second thesis is that the number of sexes is not a distributive property – it does not apply to the individuals that make up a species. This is because the biological sex of an individual is a process, and a process which can follow many different trajectories. By way of illustration, the Eastern Blue Groper has two sexes, and a life cycle in which individuals first become female and then later switch to male, but it does not follow that for a specific fish on a specific day there is a definitive answer to whether that fish is male, female or neither. In conclusion, I will suggest that the number of biological sexes in humans is a matter of little if any relevance to the many pressing ethical and political questions about sex and gender in contemporary society.”

Paul Griffiths is Australian Research Council Laureate Fellow and Professor of Philosophy at the University of Sydney. A philosopher of science focused on the life sciences, he heads the Theory and Methods in Bioscience group at the Charles Perkins Centre, a multidisciplinary
research institute examining lifestyle-related disease, and the ARC Laureate project ‘A Philosophy of Medicine for the 21 st Century’.

He is a Fellow of the American Association for the Advancement of Science, of the AustralianAcademy of the Humanities, and of the Royal Society of NSW. From 2011-13 he was President of the International Society for History, Philosophy and Social Studies of Biology.

His publications include:

(1997) What Emotions Really Are: The problem of psychological categories. University of
Chicago Press

(1999). Sex and Death: An Introduction to the Philosophy of Biology. University of Chicago
Press (with Kim Sterelny)

(2013). Genetics and Philosophy: An introduction. Cambridge University Press (with Karola

Personal website: