Although the roots of constructivism are most often attributed to the work of Jean Piaget, constructivist tenets emerged much earlier in history as seen in the writings of Giambattista Vico, who declared in 1710, "The human mind can know only what the human mind has made" (von Glasersfeld, 1995, p. 21). Noddings (1990) maintains that constructivism also emerged from the work of Neisser (actpsychology), and Chomsky (innate linguistic structures of mind). Noddings argues that constructivist emphasis on the learner as central emerges from Chomsky's and Piaget's theories of an epistemological subject: "an active knowing mechanism that knows through continued construction" (Noddings, 1990, p. 9).