Nabokov’s lecture on Proust reveals his marked interest in the French novelist’s unique sense of characterization. Nabokov first insists on the exclusively fictional nature of Proust’s characters, which is a point often debated. The first part of this chapter tries to clarify Nabokov’s position on the subject. Surprisingly ignoring the remarkable linguistic identity of Proust’s characters, Nabokov’s attention then exclusively focuses on the visual, varying and fragmentary perceptions to which Proust’s characters are submitted in the novel. The professor’s partial analysis, which relies on the use of a complete set of optical imagery, testifies to his strong interest in what he calls a ‘literature of the senses’ among which sight is crucial. ‘I do not think in any language. I think in images,’1 he once famously declared; and his lecture on Proust, which illuminates the prisms developed by Proust’s characters, also reveals his own bias as a novelist.