This chapter surveys broad themes in the late ancient and medieval use of Pythagoras and the Pythagoreans beginning with a summary of Pythagoras' quadrivial legacy, followed by a resume of the music-theoretical heritage of Pythagoras musicus, and the natural philosophical heritage of Pythagoras physicus. Boethius begins the Fundamentals of Arithmetic with an account of philosophical knowledge from the standpoint of ontology. Fully in accord with what Proclus explicitly deems a Pythagorean classification of the mathematical sciences, Boethius divides the objects of mathematics into discrete quantity and continuous quantity. Cosmic music concerns the harmonic structures and periods of the celestial bodies, the delicate balance of the four elements, and the cyclical succession of the seasons. Undoubtedly the most important of Boethius "Pythagorean" legacies is his presentation of Pythagorean music theory in the Fundamentals of Music. There are two hints one lexical, the other contextual that Boethius intends sensus as sense perception.