This work articulates two thesis: one Socratic and one Platonic; and displays how the first one is heir of the second. The Socratic one is called the principle of priority of definition; the Platonic one is the Recollection theory. The articulation between both theses is possible due to the Meno’s paradox, which makes a criticism on the first thesis, but it is solved with the second one. The consequence of this articulation is a new interpretation of the Recollection theory, as a theory of knowledge acquisition that depends, mainly, on a distinction between knowledge and true opinion. To conclude, a new interpretation of the knowledge/true opinion distinction is displayed –not in the traditional fashion, evaluating the propositions one by one, and in an atomic way–, but as big blocks or chains of propositions shaping knowledge through explanatory reasoning (aitías logismós).