In this text we will attempt to bring out the way in which Bühler’s conception of metaphor, based on the famous «model of the double filter», is consistent with his general theory of signs, whose fundamental axis is constituted, as is well known, by the Organon Modell. The latter affords clarification of the specificity of metaphor in its relation to the concepts of «field» and «functions» to which the «production» of signs is articulated. This specificity in turn clarifies the «creativity» proper to metaphor, which renders it irreducible to other instruments of sign production, thus providing it with a fullness which is as rich as it is irreplaceable.