Tristram begins, as promised, with the Slawkenbergius tale, a story about a traveler with an exceptionally long nose. He then returns to his father, who is still lying across the bed, but begins to rouse himself and expostulate about his afflictions. Walter decides that the misfortune of the crushed nose must be counteracted with all the force of an exceedingly propitious name: he settles on "Trismegistus."
Walter calls the day's events "a chapter of chances," and so prompts Tristram to review the list of chapters he has promised the reader: on knots, whiskers, the right and wrong end of a woman, wishes, noses, and modesty. He adds to the list a chapter on chapters, which he delivers immediately as his father and Uncle Toby walk downstairs. It takes several more chapters to get them all the way down the stairs, during which time they contemplate the greatness of the name "Trismegistus" and speculate on the difficulties of marriage and childbirth.
Tristram discusses with the reader the fact that he is in the fourth volume of his life story and has only gotten to the first day of his life. Some quick calculations reveal that at the current rate of one volume a year, the length of his life is growing faster than he is telling it. Rather than progressing, he is actually losing ground: "the more I write, the more I shall have to write," he marvels, pointing out that the same holds true for the reader.
Susannah rushes in with the news that the child has gone black in the face. She needs to know the name he is to be given so that he will not die without being baptized. Walter hesitates for a moment, debating whether to risk such a great name on a child who might not live to reap its benefits. But since there is no time to be wasted, he sends Susannah with the name while he dresses himself. But she proves, as Walter had feared, to be a "leaky vessel"; she can only remember the first syllable to tell the curate. He christens the baby "Tristram," impatient of Susannah's objections. When Walter learns of the mistake, he walks calmly out to the fish-pond, surprising everyone with his composure. Remaining behind, Toby and Trim find a hole in Walter's theory about the importance of Christian names, reflecting on the fact that names actually make very little difference in battle. When Walter returns to the house, he delivers a speech on the systematic manner in which he has been persecuted in the matter of this child.
They send for Parson Yorick, in order to inquire whether a re-christening is possible. He declares himself no "canonist" and suggests that they consult Didius, the church lawyer. Tristram then omits a chapter (skipping from 23 to 25) and staunchly defends his privilege of doing so. He tells at great length what would have been in the chapter before returning us to the dinner of scholars. The issue of the un-naming is put off by a comic incident in which a roasted chestnut has fallen into Phutatorius's pants and burned him. He blames Yorick for the incident, demonstrating the parson's tendency to make enemies unwittingly. After treating the burn by wrapping it in a page just off the printing press, the learned men resume the question of the naming accident. After lengthy debates they conclude, irrelevantly, that parents are unrelated to their children.
Walter Shandy actually enjoys these circular academic discussions greatly, and only when he returns home does he recall his miserable afflictions. He is immediately distracted from them again by the arrival of a letter naming him as the recipient of a legacy of a thousand pounds, left to him by Aunt Dinah. He muses for some time about how to spend the money, feeling torn between sending Tristram's brother Bobby on a Grand Tour of Europe, or making some capital improvements to the Shandy estate. His indecision is relieved, however, when the news arrives that Bobby had died. Tristram seems to exult in that fact as the volume closes, stating that he dates the proper beginning of his "life and opinions" from the moment he became the family heir. He teases the reader, once again, with the promise of Uncle Toby's love affair, calling it "the choicest morsel of the whole story."