The Gibbs Building was the site of a philosophical confrontation between Ludwig Wittgenstein and Karl Popper in 1946 – famously known in literature as "Wittgenstein’s Poker" by David Edmonds and John Eidinow (Ecco Press, 2001).

On the left the King's College Chapel.

External link: King’s College / Gibbs Building

Sources:

• Edmonds, D., & Eidinow, J. (2001). Wittgenstein’s Poker: The Story of a Ten-Minute Argument Between Two Great Philosophers. Ecco.
• Monk, R. (1991). Ludwig Wittgenstein: The Duty of Genius. Vintage.