In view of some recent research,¹ the stage would seem to be set to make a beginning with a long-standing suggestion of Professor Gilson to compare Descartes' doctrine on distinctions with that of Francis Suarez.² Accordingly, one would expect that the immediate point of departure for such a comparison would be their respective interpretations of the formal distinction of Duns Scotus. This would then introduce the more formal discussion of distinctions in each man. A closing consideration should then be devoted to the doctrine of each on essence and existence since this is the context in which Descartes frames a very important statement of his position on distinctions. In short, then, one should confront Descartes on Scotus, then on distinctions and finally on essence and existence. The same confrontation should then be made with Suarez.