Nabokov famously described Lost Time in his Lectures as, "The transmutation of sensation into sentiment, the ebb and tide of memory, waves of emotions such as desire, jealousy and artistic euphoria -- this is the material of the enormous and yet singularly light and translucid work." Which I probably agree with. The text as a whole does have a certain lightness despite its length and "heavy" subject matter.
Delauze moreover in his rather brilliant Proust & Signs (1972) characterized Lost Time as, "a prophesy about the sexes, a political warning that reaches us from the depths of the Dreyfus Affair and the First World War, a cryptogram that decodes and recodes all our social, diplomatic, strategic, erotic, and aesthetic languages… a metaphysical treatise, a delirium of signs or of jealousy, an exercise in training the faculties."
For Deleaze Lost Time is essentially an experimentation in the interpretation via the complex mechanism of memory (in all its various permutations) of signs -- gestures, sensations, love, art -- emitted by the numerous objects of the novel. It is by way of the communication of signs through time and text that the work, according to Deleauze, finds both its multiplicity as well as its unity.
We note that for Deleaze the genius of Lost Time is not its ability to appropriate meaning to a specific object, but that it's author invites the reader take part in this process of interpreting, of uncovering truth. In other words, the text, taking on the form of a 'literary machine', is productive.
Thematically then we are faced broadly speaking with the interaction of time and memory in search of truth, meaning, essence.
Which leads us to briefly to account for the narrative, which, divided into 3 unequal parts, the middle -- a love affair between a cultured, though somewhat superfluous, aristocratic by the name of Swann and a 'well- kept' ex-courtesan called Odette -- taking up the bulk. The beginning and end retrace the narrator's childhood in a Parisian suburb called Combray, where the anticipation of his Mom's good-night kiss torments him (foreglimpse of Swann's desperate affair with Odette) and he is introduced to one of his future love interest, Odette and Swann's daughter Gilberte, among other things.
'Swann's Way,' besides being the title of the novel, is an allusion to one of two routes, the other being
the 'Guermantes Way,' which the narrator and his family take during their walks in idyllic Parisian countryside.