The paper attempts to reconstruct Vlastos’ method of research into the history of philosophy using his Degrees of Reality as a case study. To do so, I rely on the extensive materials available in the Vlastos Archive. Through the palimpsest of superimposed revisions in his documents as well as the letters exchanged with his colleagues, I will go through the gestation of a whole new perspective in dealing with Plato’s conception of the reality of abstract objects. Furthermore, the focus on (...) the process rather than on the results will provide an inside view on Vlastos’ ground-breaking use of analytical tools in developing research in the field of history of philosophy. (shrink)