This book offers a reconstruction of the early Stoic doctrine of prolepsis, revealing it to be much closer to Platonic recollection in certain respects than previously thought. The standard interpretation of prolepsis as preconceptions is inconsistent with their status as criteria of truth. Rather, prolepsis is a form of tacit knowledge that requires articulation and systematization. This reconstruction is supported by a comprehensive collection of texts relating to prolepsis from Epicurus to Alexander of Aphrodisias.