In contrast to Stein's formally challenging later works, the narrative style of Three Lives is relatively straightforward. Stein wrote in The Autobiography of Alice B. Toklas of an envoy from the book's publisher who was surprised on visiting her to discover she was American, and that she assured him the foreign-seeming syntax was deliberate.
Stein admired in Flaubert and painter Cézanne their focus on working-class subjects, and their greater devotion to their means of expression over a strict representation of their subjects. Stein wished to break from the strict naturalism then in vogue in American letters. Her brother Leo had drawn her attention to compositional aspects of Cézanne—that Cézanne focused on the spatial relationships of the figures depicted rather than on verisimilitude. Stein focused on the relations of movement between characters, and intended for each part of the composition to carry as much weight as any other.