AS THE STACK of fiction by my bedside dwindled slowly over the last few weeks, I still felt like a person with a sweet tooth who had been given every sugary confection to satisfy her craving except the one thing she really wants: chocolate! What I was suffering from, I finally decided, was a peculiar phenomenon in American fiction that I have come to label the Main Character Syndrome - a phenomenon exemplified by that empty feeling left novels and by stories which have one interesting, well-realized main character but little else to satisfy a hungry reader. You may notice it after reading any short story by Anne Beattie or novels like Mary Gordon's Final Payments or Philip O'Connor's Stealing Home - fiction in which people don't seem to communiate with each other. In any case, the failure of contemporary writers to create more than one living, breathing human being seems to me to be a failure of imagination, an inability to get outside oneself (since these protagonists often seem to be autobiographical in varying degrees) to connect with anyone else. And yet it occurs to me that the fact that The Main Character Syndrome has as far as I know, gone heretofore unremarked may indicate just how out of stip I may be.

Fortunately, however, I will not go unsatisfied, not as long as there is a writer like Henry Bromell and characters like the Richardsons, the family he has brought to life once again in the four stories of I Know Your Heart, Marco Polo. The present collection, all previously published in The New Yorker, is a continuation of the story begun in The Slightest Distance, which won Bromell a Houghton Mifflin Literary Fellowship when he was still in his early twenties.

The Richardsons are on the surface an unremarkable family, almost too good to be true: Sam, a successful career diplomat, a loving and concerned husband and father; Laura, the beautiful, intelligent wife and mother; Scobie, Matthew and Quentin, the three bright, sensitive sons whose idea of rebellion seems to be smoking a little dope now and then.

Yet the Richardsons capture our imagination, draw us into their lives and become real people. The reason, I suspect, has to do with something Laura tells Sam when they are courting, discussing their favorite painters and writers: "'I love Fitzgerald and Twain because they both see something else, another drama more beautiful than our own, playing within our life.'" So does Henry Bromell.

Within the comfort and security of this family's life, the drama that is playing is the age-old one of the quest - each family member living out his individual quest for love and romance, for truth, for identity and a sense of one's place in relation to those one loves and to the world. Each of the stories is in some sense concerned with travel, both inner and outer, and the title story takes its name both from the most famous traveler of them all and from a game that Scobie, the eldest son, recalls from childhood.

Although it is the journey of Scobie, the writer, from childhood to adulthood that is in some ways at the center of these stories, it is part of Bromell's achievement that Scobie is presented in relation to others - in order for Scobie to know his father, his mother, his brother, his wife, the reader must know them also.

Nothing much remarkable happens. Scobie goes on his first trip alone. Scobie's wife ponders her marriage. Laura considers her life with Sam and the possibility of having an affair. Sam, a diplomat who wanted to be a painter, assesses the meaning of his past and future and is disappointed: "'You know, I used to think Pa was so strong, but now I look at him nodding in front of that goddamn television and think, He's weak. He's nothing. Bones adn bones. He's no idea why he's alive. Then I look at myself and think, You're not much better, Sam.'" And yet that admission is followed by another statement, equally true: "'I'm your father, Scobie,' he said. 'That's all.'"

That is the last line of the title story. The story which follows, "The World in a Room," takes that last line and attempts to show its wealth of meaning through juxtaposing the adult Scobie's memories and imaginings of his father with Sam's recollections of his own youth. One sees in Scobie's painterly, impressionistic scenes, and in Sam's, just how much it has meant to be Sam Richardson's son.

The stories are not flawless. That juxtaposition of scenes in "The World in a Room" is at first slightly confusing and the bewildering conclusion to the final story, "Travel Stories," seems to be a cheap trick that a writer of Bromell's talent doesn't need.

But these are small faults in stories which, taken together, fill the reader with pleasure and remind us that, after all, one truly becomes oneself only in relation to others. CAPTION: Picture, of Henry Bromell; Copyright (c) Jade Albert