Kolya Krassotkin, a widow's only child, is a mature and independent thirteen-year-old with a reputation for being exceptionally daring and imprudent. He is also the boy whom earlier Ilusha stabbed with a penknife; but, good-naturedly, Kolya has never held a grudge. He has been training a dog, Perezvon, to do complicated tricks.
On the day before Dmitri's trial, young Kolya is staying with two children of his mother's tenant. He feels uneasy because he has an urgent errand to attend to and leaves as soon as the servant returns. His errand turns out to be a visit to Ilusha. Kolya knows that Alyosha has arranged for other boys to visit the dying Ilusha every day, but until today Kolya has never visited the boy.
He arrives at Ilusha's with a friend, Smurov, and asks him to call Alyosha outside; he has a great curiosity to meet Alyosha. The two meet and immediately become good friends, especially because Alyosha treats Kolya as an equal. Kolya explains to his new friend about Ilusha's background and tells him that once they were fast friends, but when Kolya heard that Ilusha fed a dog a piece of bread with a pin in it, he tried to punish the boy. The punishment backfired, however, and Kolya was stabbed with the penknife. Since this happened, however, Ilusha has come to feel very bad about the dog, Zhutchka.
Alyosha takes Kolya inside, and Ilusha is overjoyed to see his old friend again. Kolya, however, begins to tease Ilusha about the dog; then, before anyone can stop him, he calls in the dog he has been training. It turns out to be Zhutchka. Everyone is delighted, and the dying Ilusha sheds tears of happiness. Kolya explains that, until now, he has stayed away so that he could train the dog for Ilusha.
A doctor from Moscow, whom Katerina has sent for, arrives to examine Ilusha, and the visitors reluctantly leave the room. As they wait outside, Kolya explains his views of life to Alyosha. Alyosha listens carefully, understanding the boy's real motives. He wants to impress Alyosha with his hodgepodge of other people's philosophies. Alyosha is sympathetic to him, though, and is especially drawn to the young boy when he confesses his weaknesses.
As the doctor leaves, it is quite apparent that Ilusha has not long to live. Even Ilusha is aware that he is dying. He tries to comfort his father, and Kolya is deeply affected by this scene between father and son. He promises Alyosha that he will come often to visit the dying boy.
Some critics have complained that in a novel of such extreme complexity and length, Book X does not contribute to the novel's unity. The section has often been said to be superfluous and a flaw in construction. A reader, they say, is anxiously concerned about Dmitri at this point, not about Ilusha. But because of the heavy chapters of violence, passion, and murder, this section can be explained in terms of Dostoevsky's inserting a healthy bit of youthful fresh air. The reader is relieved from the strain of contemplating Dmitri's fate.
This relief, however, does not explain all the charges leveled against this section of the novel. It does not, for example, explain an obvious change in tone. Here, Dostoevsky inserts the most overt sentimentality in the novel. He seems to play with the reader's emotions, and much of the pathetic background material of young Kolya's life is not central to the novel except in the very large perspective of establishing him as the person whom Alyosha will train and who will become one of Russia's future citizens, entrusted with the ideas of Father Zossima.
Perhaps the real purpose of the section is this: Dostoevsky is showing Alyosha as he moves among Russian youth, quietly influencing their lives as a living example of Father Zossima's philosophy. The hope of Russia lies in the young and in the common people, and Alyosha teaches Kolya much in this section. He meets him as an equal and offers him understanding and trust; he teaches Kolya that one cannot judge Ilusha's father, saying that there are people of rare character who have been crushed by life. The buffoonery of Ilusha's father, he says, is only the man's way of being ironic toward those who have humiliated and intimidated him for years.
Alyosha also instructs Kolya in what a man can learn from another. Because Alyosha accepts all as equals, even Kolya, he kindles a responsive chord of love. By his quiet examples, Alyosha corrects immature views without arousing animosity. He is, for example, careful not to denounce Kolya's potpourri of philosophy; instead, he simply explains that although he disagrees, he does not have contempt for Kolya's ideas. By the latter's response, it is obvious that he will become one of Alyosha's strongest disciples.