. This essay is a reflection on the key issue raised in Lakoff and Johnson's book Metaphors We Live By, i.e. the capacity the metaphor has to produce knowledge. . We first survey and then go through the positions of several authors regarding the cognitive role of the metaphor, and we then propose to explicate these positions as well as go beyond them while developing our own. . These positions are inscribed in a scheme listing: - pros and cons mutually exclusive, - compromise and rejection more or less intermeshed. . We will finally demonstrate that, far from offering new perspective by reinstating metaphor in science, Lakoff and Johnson deprive themselves and ourselves of some of the means as well as of a few fields of knowledge.
