The three brothers are Dmitri, Mitya, twenty-eight years old, Ivan, and Alyosha, twenty. None was raised by their father, and each came out of that neglect by a different path: Mitya through sensuality and his wounded honor, Ivan through a closed intelligence, Alyosha through faith.
Mitya is the son of Fyodor's first wife, forgotten in a servant's hut and then passed from hand to hand. He grows up disorderly, a soldier and a reveler, and believes he has a fortune that his father has already spent. Sensual and generous, he declares himself a Karamazov and says that falling head over heels is, for him, beauty. He competes with his father for the woman Grushenka, and the debt to his fiancée Katerina Ivanovna consumes him.
Ivan and Alyosha, sons of the second wife, were taken in by a general's wife and then by a benefactor. Ivan grew up gloomy and withdrawn, studied the natural sciences, and wrote an article on ecclesiastical courts that pleases clergy and atheists alike. He accepts God, but not the world. Alyosha is the novice of the elder, loved by all, who does not want to be anyone's judge and chooses the monastery because he wants faith whole. The elder sends him, as he dies, to live in the world.
A fourth son, whom no one acknowledges, is the servant Smerdyakov, born to a holy fool, Lizaveta, and whom the town attributes to the old man. Rakitin sums up the family in three words: sensual, covetous and holy fools. Alyosha, with an expression of Father Paissy, calls this common trait the strength of the Karamazov earth.