A Russian man was hospitalized Sunday after being shot at close range with rubber bullets over a dispute on the work of Immanuel Kant.

Kant is most well known for his work “Critique of Pure Reason.”

Two men were reportedly in line to buy beer in the Russian town of Rostov-on-Don when they struck up a conversation about the Enlightenment-era philosopher. After some disagreement, the two men started brawling before one produced an “air gun” and began firing rubber bullets at his interlocutor.

The victim is in the hospital for non-life threatening wounds. The shooter was apprehended later and faces up to ten years in prison.

The point of contention in Kant’s work that caused the dispute is unknown. But whether or not “shooting someone in the face with rubber bullets” meets the criteria for a categorical imperative seems to be a leading suspect.

[H/T ABC News]