[5][8] In 1997, Kagan published a textbook, Normative Ethics, designed to provide a thorough introduction to the subject for upper-level undergraduate or graduate students.

[1] In 2010, Yale University reported that Kagan's "Death" course had made him one of the most popular foreign teachers in China.

Kagan debated the topic "Is God necessary for Morality" with analytic philosopher, theologian and Christian apologist William Lane Craig at Columbia University.

It was that Craig's arguments were shown to be mere emotive talking points based on highly dubious premises".

[13] Richard Carrier, an author and activist whose works focus on the historicity of Jesus, atheism and empiricism, cited this debate as one of Craig's two biggest losses, along with one with physicist Sean M.

Craig also wrote:[15]I did respond briefly to Prof. Kagan's view, Alexander, but I didn't press the point because our hosts with the Veritas Forum had made it very clear to me that they were not interested in having a knock-down debate but a friendly dialogue that would foster a warm and inviting atmosphere for non-believing students at Columbia.