IV
Not only the pragmatism and the radical empiricism of James, but the idealism of Royce and the more recent movement of neo-realism are largely indebted to Peirce.
It may seem strange that the same thinker should be claimed as foster-father of both recent idealism and realism, and some may take it as another sign of his lack of consistency. But this seeming strangeness is really due to the looseness with which the antithesis between realism and idealism has generally been put. If by idealism we denote the nominalistic doctrine of Berkeley, then Peirce is clearly not an idealist; and his work in logic as a study of types of order (in which Royce followed him) is fundamental for a logical realism. But if idealism means the old Platonic doctrine that "ideas," genera, or forms are not merely mental but the real conditions of existence, we need not wonder that Peirce was both idealist and realist.
Royce's indebtedness to Peirce is principally in the use of modern mathematical material, such as the recent development of the concepts of infinity and continuity, to throw light on fundamental questions of philosophy, such as relation of the individual to God or the Universe. At the end of the nineteenth century mathematics had almost disappeared from the repertory of philosophy (cf. Külpe's Introduction to Philosophy), and Peirce's essay on the Law of Mind opened a new way which Royce followed in his World and the Individual, to the great surprise of his idealistic brethren. In his Problem of Christianity Royce has also indicated his indebtedness to Peirce for his doc-
