Three, Two, One: Counting Plato’s Principles (Again)

Why do ancient authors differ so markedly in the number of principles they ascribe to Plato? This article surveys ancient Platonist and Pythagorean accounts that posit anywhere from six principles down to one. It proposes three progressively stricter criteria for the term ‘principle’ and maps these onto the ancient testimonies. In so doing, it reconstructs the argumentative choices that drove the reduction in the number of principles. The study also brings to light a range of underexplored texts and authors whose formulations of the first principle’s superordination helped narrow the term ‘principle’ and thus propel the shift towards the Neoplatonic doctrine of a single first principle.