A dialogue between psychoanalysis and quantum physics requires, like every interdisciplinary exchange, respect for the heterogeneity and the specificity of each discipline, which presupposes a prior epistemological questioning. More often than not it is at a metaphorical level that psychoanalysts have recourse to terms and/or concepts borrowed from other sciences to support their theoretical elaboration. The author provides several examples. To question the legitimacy, the limits and interest of this recourse, a rigorous approach to metaphor - or rather the process of metaphorization - is necessary. After recalling its characteristics at the linguistic level, while pointing out that for its realization metaphor is the only rhetorical stylistic figure that requires the reference to an intermediate term, the author looks at the psychoanalytic approach to it by questioning this process in the light of some clinical sequences in order to understand the links with the paternal function, in particular, its function of producing thirdness and its inhibiting function.