Lily Hu is a PhD candidate in Applied Mathematics and Philosophy at Harvard University. She works in philosophy of (social) science and political and social philosophy. Her dissertation project concerns causal theorizing about the social world, in particular reasoning about the “causal effect” of social categories such as race and sex, and the relationship between this kind of causal theorizing and normative theorizing about core ethical notions such as discrimination and fairness. Previously, she has worked on topics in machine learning theory and algorithmic fairness.