Contrary to what one might expect, the Mythologiques do not open with a definition of myth or religion, but rather with the statement of a very general philosophical problem. The first lines of the first volume in fact propose to define the terms of a particular type of concrete logic; for, without forgetting or denying the sensible qualities of things, this logic will first be constructed on the linguistic signs endowed for the moment with an unusual definition:

To understand this definition, from which we especially cite the affirmation about the reciprocal transparency of the linguistic sign, the logical category, and the sensible quality, we must try to bring together the ensemble of Lévi-Straussian philosophical postulates.