"Second Thoughts" is a complex, stream-of-consciousness novel that unfolds during a train journey from Paris to Rome. The protagonist, a businessman, is traveling to meet his mistress, but as the journey progresses, he becomes increasingly introspective and starts to question his decisions. The narrative is nonlinear and fragmented, mirroring the protagonist's mental state, and the novel explores themes of time, memory, identity, and the nature of reality.

The 1964th greatest book of all time