Oresme's proof of the density of rotations of a circle through an irrational angle (Q1319120)

On the assumption of incommensurable velocities, Oresme shows in Ch. 2, Prop. 4 of his Tractatus de commensurabilitate vel incommensurabilitate motuum celi that there is no part, or sector, of a circle so small that two mobiles could not have conjuncted there in the past; and in which they cannot conjunct in the future. In his treatise the author shows that Oresme was in the possession of all the arguments needed for the proof to be conclusive.