Hi, there! I'm Raffi. Welcome to my website. I live in beautiful Philadelphia, where I teach at the University of Pennsylvania. I also write about European philosophy's early modern period, roughly 1600 to 1800.

I grew up in the suburbs of New York, but also in London. Perhaps it is not surprising that, in the history of philosophy, I am most interested in authors who imagine themselves to belong to multiple worlds.

I went to college at Johns Hopkins. After a year in the tech-politics scene, I fell in love with teaching and went off to do a Ph.D. in philosophy at Princeton. I’ve been teaching at Penn since 2015.

You can reach me at raphael.kl@gmail.com and follow me on Twitter and academia.edu. Here’s my CV.



My research focuses on the philosophy of Benedict de Spinoza (1623-1677). I am currently writing a book, Spinoza on Becoming Eternal, about the influence of Aristotelianism and Platonism on his metaphysics and philosophy of language.

My article “Spinoza's Metaphysics of Time” is now out in A Companion to Spinoza (ed. Yitzhak Melamed, Blackwell, 2021).


I teach interdisciplinary courses at the University of Pennsylvania, in the Integrated Studies Program. This program is based on the idea that people can become bolder, more creative thinkers by developing fresh, interdisciplinary ways of seeing.

As a postdoctoral teaching fellow in the program, I’ve team-taught courses that blended philosophical and neuroscientific perspectives on education and curiosity, as well as ancient and modern perspectives on rebellion, poverty, and evolution.

Other courses I've taught at Penn: Introduction to Modern Philosophy, Introduction to Ethics, Ethics and Language, The Philosophy of Love and Sex, Philosophy of Science, and Philosophy of Social Science.

In the spring of 2013, I co-taught a course in literature and political thought at a youth correctional facility in Bordentown, N.J.

How to reach me

Email me: raphael.kl@gmail.com.