In the Introduction to A Theory of Semiotics, Eco identifies the need for a general semiotic theory based on his claims that “the whole of culture must be studied as a semiotic phenomenon,” and that “all aspects of culture can be studied as the contents of a semiotic activity” (22). This comprehensive theory must be applicable across wildly diverse disciplines. To accomplish this, Eco advocates an inductive approach, wherein one examines the underlying similarities between various disciplines to arrive at a theory, rather than a deductive approach, wherein the fields are examined in terms of precepts. Eco, in keeping with his own varied interests (his oeuvre includes a little of everything), proposes “a unified method of approach to phenomena which apparently are very different from each other, and as yet irreducible” (8). Thus, Eco wants to develop a theory that describes the sign-function as it applies to fields as varied as zoosemiotics, tactile communication, codes of taste, languages (natural, written and formalized), text theory and mass communication (9-14).
Eco briefly describes his position in terms of other semioticians and anthropologists, and he is particularly careful to acknowledge his debts to the theories of Sausurre and Peirce while identifying their fallacies. Eco cites Saussure’s distinction between signifier/signified as useful, but believes that it was never properly articulated; the signified was left “half way between a mental image, a concept and a psychological reality” (14-15). Additionally, he disapproved of Saussure’s insistence that natural signs (e.g., red spots as a signifier for measles) were not worth consideration. This “fetishized threshold” (19) inspired in semioticians an undue focus on artificial signs, which Eco hopes to overcome by expanding the field of applicability. He lauds Peirce’s theory as more comprehensive and indicates that Peirce’s abstractly conceptualized subjects influenced his own constructs involving non-human interaction (e.g., machine-to-machine communication).
Additionally, Eco defines signification, which involves coding, and communication, which involves sign production, an important distinction that will shape the theory he strives to develop throughout the rest of the book. Signification, or the developing of a code, always precedes communication, which transmits the code. He explains that, “every act of communication to or between human beings…presupposes a signification system as its necessary condition” (9). Therefore, semiotics, “which studies all cultural processes as processes of communication” must be examined in terms of its underlying structure, or signification system (8). Eco claims that, “the whole of culture is signification and communication and that humanity and society exist only when communicative and significative [sic] relationships are established,” a principle he illustrates with examples from primitive and capitalist societies (22). Finally, Eco is careful to point out that his is not a reductionist theory by reminding us that, “it is not …that culture is only communication and signification but that it can be understood more thoroughly if it is seen from the semiotic point of view” (27).