Raphael, School of Athens, 1509-11. detail, Vatican Museums (6) (48759441642)

The seated figure of Pythagoras is shown writing in a large book, while a youth holds a wooden tablet displaying a diagram of harmonic intervals. Behind him, the turbaned scholar Averroes leans forward to observe, and a figure in a white robe looks directly at the viewer. The scene illustrates the transmission of mathematical and musical knowledge through study and observation.

This group represents the foundation of the Quadrivium, specifically Arithmetic and Music. Pythagoras's presence connects to the Neoplatonic belief in a universe ordered by number and harmony, a concept central to the 'Music of the Spheres' and Renaissance natural philosophy.