Departmental Research Seminar

Our departmental research seminar talks will take place on Wednesdays during term time from 15:00 to 16:30, in room 005, 48 Old Elvet, Durham, DH1 3HN.

Our speaker this week is Professor Letitia Meynell (Dalhousie).

Title: "The Metaphysics of Sex and the US Trans Athlete Ban – A Biological Response"

Abstract: In the fall of 2025, a group of 24 philosophers submitted an amicus curiae brief to the Supreme Court of the United States in support of efforts to ban trans women and girls from participating in women’s and girls’ sports. The amici philosophers identify their interest “in seeing the law be formulated using clear, precise and principled distinctions, rather than unclear, vague and invidious ones.” They approach their argument by “familiarizing the Court with a general philosophical distinction, between more and less ‘natural’ categories, which in their professional judgement is highly relevant to problems of categorization in general, including in the natural sciences and mathematics” (1). Though not directly citing the brief, the Supreme Court majority, which released its judgement in June 2026 in effect agrees with the amici philosophers, insofar as they eschew carefully engaging the biological facts but appear to assume brute natural kinds—a fact that Justice Sotomayor emphasizes in her opinion (which dissents in part).

In this presentation, I will lay out the basic metaphysical and biological arguments offered by these philosophers and explain why their positive suggestion for distinguishing sexes is not merely unsound but unworkable. While there are clearly legal, political, and moral arguments to be made against the position defended in this brief, my presentation will focus on the claims about the basic ontology of sex differences that they offer (drawing from some of my own work on sex categories).  I will conclude with some reflections on what philosophers who write amicus briefs owe the courts and the rest of society when they do so.