Somewhere past the Puritan Ethic, en route to the Brave New World, "something went wrong," says Maxine Schnall, "with our culture's value system."

Victims of this "cultural shipwreck," says the Philadelphia-based social psychologist and writer, are everywhere:

"The desperately lonely people in bars searching for intimacy; the joyless pleasure-seekers taking Quaaludes, cocaine and trips to Club Med; the parents anguishing over model children who have vanished into cults; the husbands who have moved out of spacious suburban homes to live a rootless existence in one-bedroom apartments and the middle-aged women left behind to run households by themselves."

And, most terrifying, she says, are psychiatrist's reports of the "increasing number of 9- and 10-year-olds who are so depressed that they want to die."

While the problem is complex, says Schnall, the root is simple: "People have lost the capacity to set their own limits.

"When we swung from being a strict, repressive society to one that tells people 'If it feels good, do it,' we were headed in the right direction, but we didn't know where to stop. We crashed through the boundaries of freedom and sailed into chaos.

"In previous times, it was a societal given that there were some things you could say 'no' to -- like extramarital sex, divorce, having a career (for women) or not having a career (for men). But now people are drowning in a limitless sea of options."

The confusion over this "values vaccuum" is the "central emotional illness of our age," says Schnall, 46, who founded a Philadelphia Wives Self-Help Group for "women undergoing culture shock" in 1974 and experienced the dilemma firsthand two years later when she separated from her physician husband of 20 years.

"Plunging into the singles' world was quite an eye-opener. I grew up in an age where sex was taboo, but now sex was very available and tenderness was not. One friend gave me good advice: 'My dear, if you don't set your own limits, Schnall decided to explore "the individual's search for limits in a confusing and hazardous world.

"But the more I delved into the problem, the more apparent it became that I could not separate the individual from the broader context of our culture life cycle."

The result of her study is Limits (Clarkson N. Potter Publishers, 340 pages, $12.95), which critics have called a "cultural 'Passages,'" limning our societal growth periods as Gail Sheehy did personal transitions.

We have been on a "cultural pendulum," says Schnall, that has swung from the "depressing '30s," to the "patriotic '40s," the "square '50s," the "revolutionary '60s," the "selfish '70s."

Successive generations, she says, have struggled toward growth -- "first by abject compliance with authority, then by total renunciation of it . . . from self-denial, people rocketed to the opposite extreme of self-gratification."

One example of our society's tendency to embrace extremes, Schnall says, is the public reaction to Watergate: "People got angry at institutions, so they threw out the values that upheld those institutions."

A fallout of this distrustful attitude, she claims, is that "people have become leery of making commitments.

"Commitment phobia is a particular problem for people between the ages of 25 and 35. They see the divorce and palimony phenomenon, and equate being committed with being entrapped."

Ironically, she notes, this emphasis on "always keeping your options open has the same net effect as the philosophy of our Puritan ancestors -- which we've rebelled against. The Protestant ethnic told us to scrimp and save, in order to be rewarded tomorrow -- which means you're not living in the here and now.

"But by avoiding commitment, to one person or one job -- because you're trying to be open in case something better comes along -- you're achieving the same net effect. You're living for the future."

This current "fear of commitment," she says, is akin to "rushing into marriage like people did in the '40s, expecting the relationship to answer all their psychic needs. The commitment addict wants to lose self by becoming a part of another and the commitment phobe fears this loss of self in an intimate relationship.

"The best way to affirm your identity and gain trust in yourself is in a committed relationship that can be a source of affection and security. But by rushing into marriage, or fleeing from it, people wind up missing that vital connection."

One reason people have tended to follow prevailing trends -- in everything from marriage to fashion, says Schnall, "is that Americans are very 'other-directed.'

"We tend to see what other people are doing and let ourselves be pushed along, instead of taking our signals from our inner compass about what is right or wrong."

This "sheep mentality" is responsible, in part, she says, for celebrity assassinations. "You get someone like Hinckley, so hungry for recognition from others, that he lives outside of any kind of limits.

"Our competitive ethic tells us that 'If you're not number one, you're nothing.' We're very bottom-line oriented. We ask people what they're earning, their S.A.T. scores. This is the kind of attitude at drives people beyond their limits."

One "promising sign" that we are working to find new, meaningful values and limits, she says, "is that people are searching for ways to be integrated. We want to have children without making parenting a second-class function, and we want to have meaningful careers without being workaholics."

The American Dream, she claims, has shifted from one of status and money ("a house in suburbia with a two-car garage") to one of personal fulfillment.

"After a decade focusing on 'me, me, me ,' we realize the importance of sharing with another and finding intimacy. Equality between the sexes and achieving a balance between satisfaction and success in personal relations and work is what society seems to be working toward."

Achieving this "humanistic balance, will entail changes in the workplace, like flexible hours and corporate involvement in day care. People can't swim upstream against the culture."