of signum. A monograph study on this question would be done by Manetti (1987). These theories have had a lasting effect in Western philosophy, especially through scholastic philosophy. The general study of signs that began in Latin with Augustine culminated with the 1632 Tractatus de Signis of John Poinsot and then began anew in late modernity with the attempt in 1867 by Charles Sanders Peirce to draw up a "new list of categories". More recently Umberto Eco, in his Semiotics and the Philosophy of Language, has argued that semiotic theories are implicit in the work of most, perhaps all, major thinkers. John Locke John Locke (1690), himself a man of medicine, was familiar with this 'semeiotics' as naming a specialized branch within medical science. In his personal library were two editions of Scapula's 1579 abridgement of Henricus Stephanus' Thesaurus Graecae Linguae, which listed "σημειωτική" as the name for 'diagnostics', the branch of medicine concerned with interpreting symptoms of disease ("symptomatology"). Indeed, physician and scholar Henry Stubbe (1670) had transliterated this term of specialized science into English precisely as "semeiotics," marking the first use of the term in English:Locke would use the term sem(e)iotike in An Essay Concerning Human Understanding (book IV, chap. 21), in which he explains how science may be divided into three parts: Locke then elaborates on the nature of this third category, naming it "Σημειωτική" (Semeiotike), and explaining it as "the doctrine of signs" in the following terms: Juri Lotman would introduce Eastern Europe to semiotics and adopt Locke's coinage ("Σημειωτική") as the name to subtitle his founding at the University of Tartu in Estonia in 1964 of the first semiotics journal, Sign Systems Studies. Ferdinand de Saussure Ferdinand de Saussure founded his semiotics, which he called semiology, in the social sciences: Thomas Sebeok would assimilate "semiology" to "semiotics" as a part to a whole, and was involved in choosing the name Semiotica for the first international journal devoted to the study of signs. Saussurean semiotics have exercised a great deal of influence on the schools of Structuralism and Post-Structuralism. Jacques Derrida, for example, takes as his object the Saussurean relationship of signifier and signified, asserting that signifier and signified are not fixed, coining the expression différance, relating to the endless deferral of meaning, and to the absence of a 'transcendent signified'. Charles Sanders Peirce In the nineteenth century, Charles Sanders Peirce defined what he termed "semiotic"