This contribution takes again the rhetorical problem of the doxa to question the semiotic idea of legitimacy. The thesis defended here consists in assessing the rhetorialc character of any speech, and, through it, the statute of doxa understood as base of the social field. From this prospect we postulate a concept of legitimacy at the principle of the semiotic activity. Topics, as center of rhetoric, is consequently proved inseparable from a concept of anthropological acceptability which conditions the meaning as a social value. It results from it a strong thesis on the doxic incarnation of language (in particular verbal) with a redefinition of the statute of meaning from the primacy of ethics.