This article explores the importance of incompleteness and the conflict that is inherent to mental life, such as they were described by Freud in his trauma theory. We analyze in particular the hegemonic presence of the metaphor of the undifferentiated vesicle (1920) in the current discourse on trauma, to the detriment of other Freudian notions that stem from his second topography (1923). Recourse to metaphors that materialize the psyche turn out in this context to be a symptomatic act in that they mask over a part of the discoveries on psychical life contributed by psychoanalysis.