Money Can’t Buy You Love : A REGULAR GUY.<i> By Mona Simpson (Alfred A. Knopf: $25, 372 pp.)</i>

Tom Owens, a laid-back biotech whiz kid, has parlayed a home-made experiment with artificial proteins into the Genesis Corp., employing 1,000 people and listed on the Fortune 500. Tom, a Bill Gates or Steve Jobs-like fictional character, made a vast fortune; 50 of his early employees and former friends became millionaires.

The “former” is a key. As in her previous novels, “The Lost Father” and “Anywhere but Here,” Mona Simpson treats of an absent father and an abandoned daughter. Absence makes a father huge. In “A Regular Guy,” Simpson extends the thought by turning it around. Tom Owens’ hugeness makes him absent: both to his daughter, Jane, and to those who once sat around with him brainstorming and shoeless.

It is not a particularly original idea but Simpson, in a novel that sparks in its confrontations and provocations yet tends to be oddly inert, develops it arrestingly. Tom’s self-isolating drive and creativity stand for a traditional though perhaps evolving male principle. He plays with his toys. The women who cope with him, suffer or see through and move past him, represent a female principle in various stages of evolving. Toys are to share.

By the end, Tom--described at one point as Mt. Rainier--is brought down to molehill size. (The author is Steve Jobs’ sister, and Tom’s loss of Genesis to a second generation of practical types recalls in some ways what happened to the founder of Apple.)

He marries, gardens and takes care of his new children. “It’s a lot more important than work,” he says and Simpson clearly agrees. The conclusion is smooth, not to say didactic, not to say smug. Fortunately, the path that takes us there is anything but smooth; and some of the rocks along the way--the setting is Auburn in the foothills of California’s Sierras, not far from Sutter’s Creek--are not only jagged but gold-bearing.

Most auriferous and jagged is Jane. In his penniless, brainstorming days, Tom and the waif-like Mary were lovers. When Mary became pregnant, Tom told her he had just started something and had to give it time. She had just started something too, and went off with it, ending up in a commune in eastern Oregon. By the time Jane was 10, Mary could no longer manage, so she sent the child to her rich and famous father.

In one of the wild jags that are Simpson making perfect sense, Mary rules out the bus. Instead, she adapts her beat-up truck so a 10-year-old’s feet can reach the pedals, teaches Jane how to use them, and dispatches her with $75, a map and a note pinned to her clothes. Jane’s drive through the night borders on the incredible, yet it is a magically believable account of what a 10-year-old can do when doing more than she can.

“The most terrible and wondrous experience in Jane di Natali’s life was over by the time she was 10, before she truly mastered the art of riding a bicycle,” Simpson writes. It makes her practical, outspoken and conservative--she always fastens seat belts--and the sharpest possible judge and corrective to her father, a Peter Pan of megaton destructiveness.

Denying for a while that she is his daughter, Tom nevertheless sends for Mary and installs them both in a modest bungalow with a barely adequate allowance of $300 a month. He is lavish and mean, and utterly self-centered. He gives former mistresses large presents for painless partings. Much of the book relates his relationship with the passive Olivia, whom he is on the verge of marrying but leaves for another woman. He figures $25,000 is a suitable breakup fee.

When he buys Mary a car it is a cheap one, and when it breaks down and she asks to borrow one of his, not only does he refuse but he stays away for three months. He can bestow but can’t be claimed. He buys a Matisse painting but soon gives it to a museum because its splendor makes it a responsibility.

A vegetarian, he buys the most expensive hothouse fruit, while Mary and Jane scrimp to get by. He whisks Jane off for a few days in Paris and seeks to impress on her that he has no interest in money or possessions but only in ideas and progress. The awful thing is that this is probably true. To prove it, he sails a high-denomination franc-note off the Eiffel Tower; and hands Jane another, inviting her to copy him.

“I’m keeping mine,” she says. Throughout the book she is clear-eyed and utterly without the deference that many of the older women characters have been conditioned to. She is Tom’s daughter and will make her claim, often--because she is a little girl--with comic effect. To demonstrate his indifference to money he shows her the uncashed checks in his glove-compartment. She asks for some; he refuses. When he preens to Mary with the claim that he is not a businessman but a poet, Jane yells from the bathroom: “A poet writes poems.”

Jane provides much of the book’s energy; many of the other characters are either too casually and vaguely introduced or else, like Mary and Olivia, they occupy a great deal of space while lacking pith. Noah, an experimental scientist confined by bone disease to a wheelchair, has considerable appeal.

He is, too obviously perhaps, Tom’s counterpart. He is also his best friend, in part because Tom cannot seduce and control him. In partnership with a brilliant woman assistant, he is working on pure research. It is frustrating and ill-paid; and he hesitates when Tom offers him a million-dollar bonus to join his company. The hesitation is wonderfully human; so is his delight with the specially equipped van that Tom gives him. Noah, in fact, is one of Tom’s channels to eventual redemption (Jane’s tart clarity is another).

Simpson makes the redemption extremely heavy-handed. To portray Noah as crippled, utterly shy about sex and a yearning virgin in his 30s--a kind woman friend finally initiates him, giving him the instant courage to propose to his lab partner--rather stretches things. It seems a stiff condition to set for a male to be acceptably human.

There is a good deal of arranging in Tom’s downfall and reform: It takes a managerial coup which, though it can account for the fall, is a bald way of getting regeneration in gear. Another strain is to have Noah’s breakthrough--he has isolated a gene, there are Nobel whispers and, should it come, his lab partner will share--coincide with Tom’s defeat. It also coincides with Jane’s getting elected as class president.

Such switchbacks might suit a fable, but they don’t work in an extended novel of manners and ideas that, for the most part, is couched more or less realistically and whose plot-line tends alternately to creak and fade. It is the smaller things that best light up Simpson’s thesis about men and women: Jane’s stubborn incandescence, Noah’s comically difficult idealism and witty snapshots of Tom as the oblivious macho intellectual-cum-entrepreneur. Also--at least for me--the incorrect factlet that the admirable characters avidly eat meat, while the deluders and deluded are mostly vegetarian.