I work in the philosophy of mind, epistemology, and philosophy of language. I examine how the psychological interacts with the social. My forthcoming work takes up issues concerning interpersonal disagreement, the normativity of attention, and ideology. 

For appointments please use my calendly page. [This is for in-person office hour appoinments only for Penn students.]

I specialize in philosophy of science, philosophy of biology, and philosophy of race.  In philosophy of science, I primarily focus on metaphysical problems in science, such as what is an appropriate way to define "natural kinds."  In philosophy of biology, I primarily focus on metaphysical problems in biology, such as whether biological populations can have fuzzy temporal parts; and whether there's any way to divide Homo sapiens into biologically real races for taxonomy, population genetics, or medicine.

National and International Honors

Member, American Academy of Arts and Science, 2021

Member, Germany Academy of Science, Leopoldina, 2021

Honorary Fellow, Wolfson College, Cambridge University, 2016

Pufendorf Medal, 2015

Cavaliere Ordine al Merito della Repubblica Italiana (Knigthood), 2007

For more information, here are my publications