Descartes' focus in Meditations is to re-evaluate the accepted scholastic system through a new epistemology rooted in doubt and scepticism. Nevertheless, Descartes does borrow from the scholastics in his understandings of God and reality; the distinction for him is the end not the means. If Descartes is associated with the divergence from Aristotelian-Scholastic thought than without a doubt Locke is the person associated with the departure from rationalism to empiricism. Before dealing with text I think it is necessary to place Descartes in his proper historical context. The preponderance of writing on the theory of personal identity in the past has been influenced by John Locke notwithstanding Descartes' understanding was a necessary departure from previously agreed upon philosophies. Descartes concept of substance is a variant of nominalism - which contrasted scholastic thought - whereby substance and accident are not distinct; this change would be fully realized in later epistemologies where thought is the foundation for knowledge.