On the evening of Tristram's conception (the first Sunday in March 1718), Mrs. Shandy asks a trivial question in the middle of that important event. The irritation it causes in his father has a negative influence on the "animal spirits" that control the makeup of the Tristram-to-be. The foundation has been laid for a "thousand weaknesses both of body and mind" in Tristram.
It was Uncle Toby who told Tristram the story of his conception; he told him also that when Tristram was young, Walter Shandy had observed many things about him that verified his opinion that the trouble had started on that fateful night. Mrs. Shandy, however, never knew or understood the slightest bit of this theory.
Tristram threatens that in telling his story he will not follow any of the rules laid down by the critics, but he realizes that curious readers want to know all the details from beginning to end. He explains that from information he has gleaned from his father's old memorandums, he is able to pinpoint the exact night of his conception. His father was "one of the most regular men in every thing he did"; for example, he wound up the family clock on the first Sunday night of every month and took care of "some other little family concernments" at the same time — once a month. The one thing and the other were always linked in his mother's mind, hence the question that she asked. He tells the day of his birth (November 5, 1718), and he says that his life has consisted of "pitiful misadventures and cross accidents," just as his father expected.
The author makes fun of the "begin from the beginning" novel by giving us the details not of his birth but of his very conception. From the first sentence he establishes his presence, that of a person with lots of opinions. He is the person and the writer who is the natural outcome of the events that he pictures for us from Chapter 1 onward. The ideas of his father have taken firm hold in his mind, and he is the embodiment of things gone wrong. In a way, his book goes wrong from the beginning: instead of giving the reader straightforward facts, he gives minute background and precise explanations about that background. He goes into detail about the details — a propensity that he has obviously inherited from his father.
In addition to establishing his own presence, he shows us without preliminaries his mother and father in bed on that evening. It is as if he has suddenly raised a curtain on the actors who are waiting to begin their performance. At their very first appearance in the book, Mr. and Mrs. Shandy are as vivid and three-dimensional as they are whenever the stage is given over to them, whether for a brief flash or for an extended sequence.
Several important motifs appear in these first chapters. One of them is the Lockean theory of Associationism, introduced in Chapter 1. Two or more ideas become associated in someone's mind; when one of these ideas occurs to him, the other occurs with it automatically. They are inseparably linked. This is a kind of "madness" that periodically springs up in Mrs. Shandy and Uncle Toby, especially in the latter, and naturally they have no control over it. Some of the funniest situations in the book derive from such associated ideas.
Another motif is the author's attention to the believability of his story. Events and conversations that he personally couldn't have witnessed are told to him by someone who was involved, or else he finds documents, letters, diaries which give him necessary facts. That is one of the ways that Tristram remains Tristram and not Sterne as an omniscient narrator.
Still another very obvious motif is the relationship established between Tristram and the reader (sometimes "Sir," more often "Madam"). The reader is always in the forefront of Tristram's consciousness, and not only when he says "Dear Reader." The reader is made to participate in the book; he finds himself face to face with the author, having questions put into his mouth and supposedly having made comments that the author must answer. Sterne hoped to get the reader to experience the impressions that Tristram writes about, rather than to stand far off and objectify them. The reader was intended not to observe but to participate with Tristram in the re-creation of Tristram's sensations and to reflect upon those sensations as Tristram was reflecting. One could say that Sterne is conducting the reader on a psychoanalytic tour of both Tristram's and the reader's intellectual and emotional being.
The dispersal of the animal spirits is the first of the accidents that befall Tristram. Its importance can be judged only by what we see in Tristram's character, but if we take Walter and Tristram's word for it, it was an accident with grave consequences.