THE SUMMER between high school and college, I fell in love. Fortunately, I didn't get the girl pregnant. Had that happened, the summer might have been so traumatic I'd have been inspired to write a book about it called The Only Thing I've Done Wrong. It didn't happen to me, but it may have happened to John Jay Osborne Jr. '67. Whether it did or not, Osborne wrote a novel based on that scenario of love and trauma and he called it, well, you can guess.

Osborne's resume looks impressive--Harvard, Harvard Law, a clerkship with a Federal Appeals Court judge in Philadelphia, an apprenticeship with a top New York law firm--and he apparently feels compelled to write about the high powered life during his leisure hours. First there was The Paper Chase, a novel he wrote while a student at the Law School. Following his stint in a corporate law firm, Osborne moved to Yale where he is now writing a book about "life in a corporate law firm," according to his publisher's press release. In between, Osborne wrote The Only Thing...

The Only Thing I've Done Wrong borrows heavily from many sources, among them The Scarlet Letter, The Last Summer, the Bible, American Graffitti, Mr. and Mrs. Bo Jo Jones, and Osborne's life. It is about San Francisco and sailing in the summer, because Osborne grew up in San Francisco and is "an accomplished sailor."

But enough of superficialities, you say, what about the book? I've already given away half the plot, and feel a tinge of guilt creeping around my shoulder as I type, so I won't tell you any more for the mere price of The Crimson. Without giving away that much, however, you might not read past the first five pages--I only made it to the crucial "I'm pregnant" scene because I was reviewing the damn thing.

Until that scene, for example, I wasn't even sure that Robert and Kate actually had made love. Before that point in the story, in fact, the issue was by no means crucial. The plot seemed to be mostly about the vague yearnings of summer love and the not-so-vague yearnings for a good clean fight down at the Yacht Club--the things of which a rich California boy's summer before college are made.

The sharp break in the book at that scene--it becomes suddenly less banal, more interesting--points up the book's major strength and weakness. From that point on, Robert's conflicts with his father are rooted in reality: someone, somehow, has to do something about Kate's pregnancy, and Robert's father, a prominent local surgeon, is a likely candidate for the task. But his father also believes firmly in a "sense of responsibility," and is extremely disappointed in his son Robert for displaying a serious failure to be responsible. One simply does not get one's friends pregnant.

The crisis between father and son, which becomes the focus of the novel and provides its organizing structure, is superbly done. The dialogue among father, son and mother rings true, moves well, and develops a depth of character behind the tanned affluent faces living by the Pacific. Men like Robert's father exist, and not surprisingly, they raise sons like Robert--bright, handsome, athletic and graceful, and totally unprepared to meet their first crisis of responsibility.

Sons like Robert don't intentionally bring on their father's responsibility lecture. They want desperately to be responsible, but they also can't understand why their fathers won't easily forgive them. The book's title comes from an unspoken plea that holds within it all the misunderstanding and confusion of an adolescent trying to cope with a serious, suddenly adult problem.

If the scenes with Robert and his father ring true, the dialogue between Robert and Kate doesn't ring at all. The exchanges are cliched, wooden, alternately boring and unconvincing. Kate's parents are conservative, blame Robert for their daughter's "condition," and seem paralyzed by shock and Puritan indignation. As such, they are stereotypes, merely providing a field for Robert and his father to joust upon.

Osborne writes well and convincingly about fathers, but badly about girlfriends. It seems entirely possible that Osborne had a combative relationship with his father and therefore can write about it, but never got his girlfriend pregnant and so has trouble writing about that.

OSBORNE'S DESCRIPTIONS of sailing, childhood and adolescent play are good, and add some breadth to the book. By themselves, his narrative of a sailing cruise down the Baja coast or of the mental torment involved in sliding down a swinging rope in his grandfather's huge hay barn don't say much of anything, but provide pleasant interludes between the fights Robert has with his father.

The Only Thing I've Done Wrong is neither as fast-moving nor as tear-jerking as Love Story, and it doesn't tell you as much about your future as The Paper Chase. It tells you about your past, or more probably, someone else's. It addresses a small audience, made up of affluent young men and their fathers, and maybe even their mothers and girlfriends. It can't tell you why you wanted to punch your father one hot summer day, or why you didn't do it, or why he later punched you, or even why you still love each other. But it can remind you of what it's like to be irresponsible in a responsible home. For that it's almost worthwhile.