I am a Professor of Philosophy at Columbia University, New York NY. In my books and papers, I focus on questions that figure both in ancient and contemporary discussions: What are values? What kind of values are knowledge and truth? What is the role of epistemic norms in ethics? Currently, I’m aiming to develop a metaethical theory that accounts for difference and disagreement (2020 and forthcoming). And I’m returning to related themes in Stoic logic and Pyrrhonian skepticism.