He was Professor Emeritus of Philosophy at the State University of New York at Buffalo, having previously also taught at Vassar, Trinity, and Union colleges, and the New School for Social Research.
Kurtz was the founder and past chairman of the Committee for Skeptical Inquiry (CSI, formerly the Committee for the Scientific Investigation of Claims of the Paranormal, CSICOP), the Council for Secular Humanism, and the Center for Inquiry. He was also involved with various other skeptic and secular humanism organizations and activities.
He was editor in chief of Free Inquiry magazine, a publication of the Council for Secular Humanism. He also founded the associated publishing house Prometheus Books.
Kurtz was a race denialist.