Tolstoy seems to have written this novella before he wrote Confessions, The Kingdom of God is within You, and The Gospel of Jesus. I would need to research that to verify the statement, but his analysis of the protagonist seems excessive. I read the Kreutzer Sonata; whew! Now I need to listen to it and to finish the other stories.

The opening of this novella takes place during a train ride. Passengers are discussing the news of the day, Pozdnyshev overhears a conversation concerning marriage, divorce and love. When one rider alludes to news about a man who killed his wife Pozdnyshev speaks up:
"'I'm Pozdnyshev, the one to whom that critical episode occurred which you alluded to, that episode in which he killed his wife,' he said, quickly glancing at each of us.

Pozdnyshev begins to tell his story, he asks "what is love?" and points out that, if understood as an exclusive preference for one person, it often passes quickly. Convention dictates that two married people stay together, and initial love can quickly turn into hatred. He then relates how he used to visit prostitutes when he was young, and complains that women's dresses are designed to arouse men's desires. He further states that women will never enjoy equal rights to men as long as men view them as objects of desire, but yet describes their situation as a form of power over men, mentioning how much of society is geared towards their pleasure and well-being and how much sway they have over men's actions. His commentary becomes both repetitive and disturbing.

After he meets and marries his wife, periods of passionate love and vicious fights alternate. She bears several children, and then receives contraceptives: "The last excuse for our swinish life -- children -- was then taken away, and life became viler than ever."
His wife takes a liking to a violinist, Trukhachevsky, whom Pozdnyshev immediately dislikes, but with whom he feels a strange connection that leads him to invite the violinist to perform with his wife, who had become the violinist's student. The two perform Beethoven's Kreutzer Sonata (Sonata No. 9 in A Major for piano and violin, Op. 47) together. Pozdnyshev is overcome by the hypnotic effect of the music. While he goes away for a few days when he returns and finds his wife "making music" with the violinist he loses control. Taking a dagger from the wall above the sofa he kills his wife with it. The violinist escapes: "I wanted to run after him, but remembered that it is ridiculous to run after one's wife's lover in one's socks; and I did not wish to be ridiculous but terrible."
Afterwards he rationalizes: "So he and his music were the cause of everything." His marriage as presented by Pozdnyshev was a shambles already, but beyond the surface Tolstoy uses this case as an argument against the goodness of beautiful art. Pozdnyshev questions the nature of the Good and what is moral echoing the divide between external Good and internal values that can be seen in the ideas of Rousseau and Kant.

Later acquitted of murder in light of his wife's apparent adultery, Pozdnyshev rides the trains seeking forgiveness from fellow passengers. After the work had been forbidden in Russia by the censors, a mimeographed version was widely circulated. It was eventually printed in Tolstoy's collected works. It is powerful even today for the questions it raises are still with us. ( )