Charles Peirce had significant interests in economics. He reworked the mathematical economic models of Cournot and Jevons in the 1870s. He conceived of the transitive axiom of consumer preferences in 1874. Peirce also developed a thesis of the cognitive efficiency of the human mind, abduction. He criticized Newcomb's economic writings. These forays into economics affected the six essays on pragmatism. These interests in economics are integrated with the meaning of the pragmatic maxim in Peirce's 1903 Harvard Lectures.