The Metaphysical Problem in Race Theory

Quayshawn Spencer


Quayshawn Spencer’s 4 p.m. lecture is available for live stream on demand at

We regret that the 11 a.m. lecture is unavailable due to technical failure during recording.

We invite you to visit Quayshawn Spencer’s website for more information on his topics at


Friday, February 14, 2020

Pre-lecture Discussion: “What is Race and Why is the Question Important?”

2:15-3:15 pm, Overton Hall

Join us for a pre-lecture discussion with Assistant Professor Brian J. Collins. The goal of this presentation and discussion is to offer an introduction to the topic and help familiarize everyone with the theme of this year’s lectures.

Tuesday, February 18, 2020

Lecture 1: When Population Genetics Meets the Metaphysics of Race

11:10 am, Samuelson Chapel

The Human Genome Diversity Project (HGDP) obtained the first large-scale sample of human genomes in the history of genetics. The results of the first study of HGDP genomes appeared in a now landmark paper in Science in 2002. The most famous and controversial result from this paper—and that we now know is robust—is that the human species naturally subdivides into five groups based on genomic similarity: Sub-Saharan Africans, East Asians, Caucasians, Native Americans, and Oceanians.

However, it didn’t take long before geneticists started asking what else are these groups? A consensus quickly arose that these groups are biological populations. However, geneticists are still split on whether these groups are races. In this talk, I argue that these five human populations are races because they are, in fact, identical to the US government’s official races. After defending my argument, I explore implications for NIH-funded clinical research in medical genetics.

Lecture 2: A Radical Solution to the Race Problem

4:00 pm, Samuelson Chapel

In this talk, I use the results of the first lecture to show that the US government’s official race talk is about a biological division of people that’s biologically real. After defending this position, I turn to applying this result to the US race debate—the debate about the nature and reality of race according to US race talk. Since its inception, the US race debate has been completely dominated by monist race theories insofar as philosophers have always argued that there is a single, correct way to characterize what race is and its reality status.

For example, the social constructionists have argued that race is a non-biological social construct that’s socially real. However, using my previous results, I show that all monist US race theories are incorrect. Instead, I show that the correct race theory for our country is one that has a radically pluralist form and content.

Spencer PhotoQuayshawn Spencer, Ph.D.

Quayshawn Spencer is the Robert S. Blank Presidential Associate Professor of Philosophy at the University of Pennsylvania. He holds both a PhD in philosophy and an MS in biology from Stanford University.

Spencer specializes in philosophy of science, philosophy of biology, and philosophy of race. In all three of his specializations, Spencer focuses on metaphysical problems, such as how to appropriately define ‘natural kind,’ whether biological populations can have fuzzy temporal parts, and whether any folk racial classification divides humans into real biological groups.

Spencer has published several journal articles on the topic of race & biology, but he’s best known for “What ‘biological racial realism’ should mean” in Philosophical Studies (2012), and “A Radical Solution to the Race Problem” in Philosophy of Science (2014). Spencer also has one published book with Oxford University Press, What is Race? Four Philosophical Views (with Glasgow, Haslanger, and Jeffers), and one forthcoming edited volume with the same press, The Race Debates from Metaphysics to Medicine.