IT HAS BEEN SAID by frustrated lovers and even meat hunters who break mirrors and fling frying pans in the morning, that men and women have been messing with each other's minds at least since Helen of Troy. And despite the computechnic heralding of this supercool Space Age of Sex, love and sex still bring on concommitant confusion, loathing, ambivalence and ugliness.

No dramas need to be enacted--especially one that never gives the answer but charges $10 anyway. Sexual Perversity in Chicago never really gets to the point. It is a trite medley of some stereotyped, six-pack guys, their neurotic quests for orgasmic relief, and creeping cynicism.

But I'm tired of "Let-me-tell-you-how-I-got-laid" stories. I've heard all about whips and delights and pederasty and binoculars. I want some answers. It's 1978. This is getting quite serious.

Some of the answers can be found over a beer at the bar around the block from the Charles Playhouse. Field work in any research is essential, but the playhouses of Boston's theater district can do no more than mimic the action going on outside their doors.

The hooker was being hassled by some drunken old family man, and she started trembling when his voice broke and he called her a cocktease.

"Look I'm with my boyfriend here, so go away."

But when he left after the two-ton bartender told him to scram, she lit up a cigaette and talked furiously about professionalism.

"They're all old men," she said. "And married. They want you to do all the things their wives can never do for them. And when it comes to the time, they don't know what they want. But I wouldn't be doing this if it weren't for the money. I just feel like I've never been loved in my entire life."

Her beautiful body was mopping up all the business in the place, and she, a professional professional, insisted that sex is never perverse, just misunderstood.

"If only people could communicate, get out of their bodies and not be afraid of themselves," she said.

The suburban business executive sitting next to me at the play laughed at every ruse in the drama, but held his tongue when it became all too real.

"I really was reached," he said, "because it was an in-depth commentary revealing some nagging contradictions in what we like to call a sexual revolution or a more carefree, problem-free era."

Sexual Perversity, David Mamet's Obie-winner, is very good at stating the hang-ups that follow society's tangled and neandrethal delineation of sex roles. There are numerous obnoxious stories behind bars and superficial sighs and women in anguish; even a cute relationship ending with the lovers calling each other "lousy lays."

Danny and Bernie (Peter Kovner and Joseph Wilkins) are two office buddies who wind up competing for the wildest story and cruelest screw, as their two female counterparts, Deborah and Joan (Deborah Strang and Laura Hepner) feed on each other's disillusionment.

Danny is really a genteel, quiet guy who takes an earful too much of Bernie's ego--enough for him to ruin his relationship with sweet Deborah. Bernie, of course, never gets beyond his graphic stories.

After an arrogant encounter with Bernie at a night club, Joan (who crosses the most neurotic and presumptuous qualities of a college preppie and a Victorian school marm) wallows through the play tangled in a carefully cultivated hatred of men, particularly those who have problems with premature orgasm.

And after shunning her roomates cynicism, Deb joins in lament and tooth-grinding agony after her own love affair with Danny. Like Debbie, Danny merges character and cro-magnon consciousness with Bernie (who thinks all women should be wrung like lemons and then "dropped like a fucking hot potato"). But enough of this soap opera.

The acting, with the exception of Strang and Wilkins, is overdone and the delicate, sincere moments are lost in superficial sighs. Strang is convincing, making her presence in the drama count, and the overblown Wilkins (no pun intended) can never really overact the part of an asshole as intolerable as Bernie.

Even Mamet's writing is appropriate, though his quick, apocalyptic flashes from situation to situation are hampered by superficial acting and several muffed blocking and lighting cues.

To tell you the truth, this play lacks deep thought and good research, such as that which can be found in talking to the hookers outside the theater.

WHAT REALLY SAVES this evening of Mamet--arguably America's hottest playwright--is the other, simpler, less garrulous drama--The Duck Variations. Not only is it funnier, more interesting, and better acted, it is deep and relevent and genuinely responsive--without being bombastic or tiring.

There is only one scene--two old Jewish men on bench in a park--and no breaks. The piece just winds up and up and up with rolling variations on melodic conversation--the kind of talk you know immigrant grandfathers share in their age.

"What a world is this?" one says with open arms. "We spend our lives doing silly things we never like to do, sending shit up into the stratosphere--but the duck, the duck, he can fly. Any idiot can learn to swim, but it takes a bird to fly."

"Even the duck must get old," the other posits.

"Yes, but nobody is getting any younger. And now we try, so stupid and futile--it makes you want to stop trying.

"But the duck, he does not worry. When the duck dies, what does he think?"

"He wants to live some more," says the other.

"Yes, but he feels no remorse and jealousy and bad feelings in death, for it is the law of life. He does not question this."

"Because the duck is part of nature," the other complains.

"So too is man part of nature. Just like the duck."

"Speak for yourself," the other says as he gazes away.

Mamet was clever to juxtapose these two plays: one drama answers the dilemmas of the other in a very sober and natural way, and George and Emil (Jerry Gershman and Ted Kazanoff) interact like a violin duet, weaving the problems of the evening and life into some simple sense.

"We get distracted," Emil argues. "The duck knows from the first moment of his life that he must fly and find a mate to into and be with until DEATH PARTS THEM. And we--we spend our lives cleaning their shit off the sidewalks."