------------------------------- "An Underachiever's Diary" by Benjamin Anastas Dial, $15.95 -------------------------------

The literary antecedents for Benjamin Anastas' debut novel are many and obvious. Like Dostoyevsky's sick man in "Notes From the Underground," Anastas' William is a social misfit, clumsy with women and work, who in a ranting, contradictory confessional decries not only his own condition but the condition of society.

Because William is the twin of a more popular, outgoing, overachieving brother, there are elements of Salinger's Buddy Glass in him. I even caught a whiff of "Portnoy's Complaint." William's parents are '60s liberals, populist elitists, who believe in psychoanalysis and free love (they walk around the house naked), and so William rebels by not qiving into his urges. He is the anti-Portnoy.

Sad to say, "An Underachiever's Diary" doesn't bear up well against the weight of its antecedents. It is a skimpy 147 pages, though Anastas has his nimble moments.

"The adult bodies I had seen looked suspiciously soft, way too white, and unbelievably hairy, like nothing that should be exposed to sunlight," says William of hi ents and their nude-gardening neighbors. Recalling himself and his brother in the hirsute mid-'70s, William writes, "Taken together, our hair could stuff a sofa, easily."

But interesting characters are introduced only to disappear. Humorous situations fizzle away. William's diary should be another of his many underachievements, yes, but not at the expense of the book itself.