 Reviews of The World and the Individual praised Royce’s philosophical acumen but raised significant objections to his conclusions. Peirce, in particular, pointedly criticized Royce’s use of logic. Royce set out to reconsider his central arguments and, at the same time, undertook an ambitious program of study in mathematical logic. In his teaching and publications after 1900, two philosophical strains came to the forefront. One was a growing reliance on formal logical and mathematical concepts as the basis for his metaphysical speculation (the first hint of this appears in the “Supplementary Essay” to the first volume of The World and the Individual). The second was an emphasis on philosophy as a means to understand the concrete phenomena of life: the nature of human society, of religious experience, of ethical action, of suffering and the problem of evil.