(((( How Do You Know ))))

The title question posed by the fumbled romantic comedy How Do You Know is open to more readings than writer-director James L. Brooks probably had in mind. The simplest interpretation is, how do you know when you're really in love? That's the dilemma faced by Lisa (Reese Witherspoon), a 31-year-old professional athlete at the end of her softball career, who bounces between two men. Should this compact, upbeat go-getter give her heart to Matty (Owen Wilson), a rich and famous major league baseball player whose vanity is offset by his sunny guilelessness and who offers great sex and good times? Or is she better off with George (Paul Rudd), a sweet but anxious businessguy who, as the naïve target of a federal investigation into business shenanigans, is watching his life fall apart? Consider the character types, consider the familiar personas of the actors who play them — Wilson the loopy blond operator, Rudd the cute brunet everyshlub — and you've got your answer even before you buy a ticket.

The deeper meaning of Brooks's title, meanwhile, is this: How do you know what the right thing to do is, both in the big picture of life and in the moment? Business ethics and family responsibilities challenge George and his father, Charles (Brooks regular Jack Nicholson, broadly over-spluttering), a hard-charging financial tycoon who also happens to be George's boss. Lisa needs to devise a new career plan now that her days at bat are over. Even George's loyal, very pregnant office assistant (Kathryn Hahn) wrestles with the ethics of sharing confidential information — as well as with the terrors of impending single motherhood.

All this to-ing and fro-ing, this trying and failing on the way to (excuse the shrink talk) self-actualization is rich material for an expansive romantic comedy of psychological substance — the kind, indeed, that Brooks has made his feature-film specialty, from Terms of Endearment and the great Broadcast News to the sour Spanglish. But something doesn't connect here. Scenes go flat, punchlines foul out. And a sympathetic but frustrated fan of the filmmaker's stories and characters is entitled to ask, why doesn't How Do You Know know what to do from scene to scene? The answer, I think, is partly structural and script-driven: the ''funny'' moments are whiffed, the dialogue is ''scene-y,'' and each reaction shot is held a second or ten too long, leaving the actors hanging. But the bigger reason may be because only one character really fascinates Brooks, and that's Lisa the athlete. Her energy is palpable. Her suitors, in contrast — especially Matty the player, who keeps a closet full of pink loungewear on his shelves for his many visiting ladies — are more plot-functional than three-dimensional, even when Rudd gives adorable, well-meaning haplessness his best, Ruddiest shot. How Do You Know asks really good questions but doesn't so much answer them as toss the ball from player to player until the clock runs out.