Lenny Bruce, striding past taboos that stood as barriers to communication, was a liberator of language. When Bruce ripped through his monologue, his audience could do one of two things: laugh in self-conscious embarassment or leave in a huff. The early '60s comedian--probably the most controversial in the trade's history--mined a rich, dark vein of American humor; he dug for the mother lode--religion, race, drugs, sex, morals. He rooted through the secret and sordid alleys of the subconscious, exposing them to an unsettlingly clear light.

By 1972, six years after Bruce died of an overdose of heroin, comedian George Carlin would safely record a nationally-distributed album on which he calmly rattled off the "seven words you can never say on television." By then, of course, the shock value had dissipated. Carlin managed to keep the words funny only by stringing them all together in one breath: "shit, piss, fuck, cunt, cocksucker, motherfucker and tits."

A lot had changed since Lenny Bruce last stood on a nightclub stage, and a lot of the change had resulted from Bruce's persistence in saying what he wanted to. Between 1961 and 1964 he was arrested four times for obscenity. The court battles that resulted from the arrests bankrupted him in 1965, ten months before he died with a needle in his arm. To the '70s consciousness, the specific grounds for Bruce's arrests seem absurd. He said words like "shit," "penis," "asshole" and "cocksucker," but he did not do so on television. He didn't cut records, he didn't wander the streets mouthing dirty words at 12-year-old girls. He used the words in a nightclub act, talking candidly about sex and about how absurd it was that words like "fuck" and acts like fucking were considered obscene when it was alright for children to watch bloody killings in movies.

Only after Bruce's death did popular wisdom recognize the importance of what he had been doing. Before that time, newspapers had often dismissed him as "dirty Lenny" the "sick comedian." But a generation that never really knew him came, in the late '60s, to view him as a great parodist and a martyr for freedom of speech. Since then many have picked up on Bruce's observations about the relative obscenity of killing and fucking. The bit has become cliche.

But accounts of Bruce's life too often ignore what he was saying while they examine what he did for the status of the dirty word in America.

Lenny Bruce drank at the wellspring of comedy, the pathos that Mark Twain once said is the source of all humor. By making jokes about people's attitudes towards unmentionables and bringing the thoughts out into the open, his jokes acted as catharsis.

For raw material Bruce drew from his own life; he didn't talk about easy subjects. When he rambled on in the abstract, he was drawing from his own experience. That quickly becomes apparent if one looks through written versions of what Bruce said onstage, and compares the routines to the personal narratives in his autobiography, "How to Talk Dirty and Influence People." In fact he writes in his autobiography, "One thing about getting divorced, it gave me an hour's worth of material. That's not bad for an eight-year investment." Bruce's hallmark was a tough laugh-or-cry honesty.

It is difficult to find any comedian to compare. First of all, Bruce was a nightclub performer, and no other stand-up comedian has received so much attention without making a mark through television, movies or records. Bruce made a name for himself during his court cases; the brouhaha that surrounded his death immortalized him. Most of what the modern public knows about Bruce comes from secondary acounts. The only first-hand records of Bruce's work are his autobiography, a posthumous collection of his material entitled "The Essential Lenny Bruce," and "The Lenny Bruce Performance Film." Although many of his engagements were tape recorded, only one was ever filmed. Dustin Hoffman, who plays the title role in the feature film "Lenny," spends more time on film as Bruce than the comedian himself spent performing on film in his entire life.

"The Lenny Bruce Performance Film," now playing at Off the Wall theatre near Central Square, records Bruce's next to last performance before his death. By then he was obsessed with his court cases--he spends most of the film reading from transcripts and explaining how his words were twisted in court, and what he really said. One of the funniest bits in the monologue is Bruce's imitation of a vice officer imitating Bruce's act for a grand jury. The cop's reaction is typical; all he can remember are dirty words.

Bruce rambles and digresses during the act. He was in bad physical shape by then. His mind often seems to work too fast for his mouth, making it a challenge to follow his train of thought. It's impossible to catch everything.

Bruce makes modern popular comedians look like lightweights. But it must be noted that Bruce did not become a mass audience comedian during his lifetime, and he would probably not make it as a nationally famous comedian today. Bruce's act could never sell records, and most of his material would be censored from television. The market for hard-core moralizing and satirizing is limited. Contemporary comedians toy with the freedom of expression they now enjoy without appreciating the power of their words to reveal, and so to help people explore and understand the unmentionable corners of their lives. The freedom to swear is a superficial freedom if it is not accompanied by an equally frank discussion of the social and moral institutions underlying the "dirty words."

When George Carlin rose to fame in 1972 with his album "Class Clown," his route was not nearly as painful as Bruce's had been. While Carlin provokes some laughter on his record by poking fun at the Catholic, Church's elaborate dogma, the album as a whole seems to be oriented towards the innocuous and forgettable thesis, "Wasn't it fun to be a kid?" Carlin is certainly successful in making people laugh, but there is no catharsis in recalling All Those Great Jokes everybody used to pull in grade school--gags like "the artificial fart under the arm" and the marathon burp. All humor does not derive from pathos. Silliness is also a consideration.

It is certainly an important consideration in current star Steve Martin's monologues. The source of his humor is about as far removed from Bruce's as one can imagine. Martin, like Johnny Carson, delivers non-jokes, gags about how his jokes flop, about the ridiculous price of admission, and about how ludicrous the comedian's job is. Lenny Bruce wove his life into the bits he performed for nightclub audiences; Steve Martin (one must assume) leaves his real life behind when he goes onstage to make a fool of himself for the audience's benefit.

Although the two comedians are an era apart in terms of both material and audience, they share a manic energy level. Martin channels his into creating absurdity; Bruce turned his attention to pointing up absurdity where it already existed in the world. Both are funny, but Bruce's humor reveals a string of little paranoias that inhabit people's minds. Both shock, but Martin's humor includes more shock simply for the laugh value of surprise.

The irony of Bruce's last years is that he went to court accused of spewing out, as he put it, "dirt for dirt's sake," but he packed into his act as much meaningful social comment as anyone has, then or since. Even though Bruce's assigned role in history is one of legitimizing and effectively legalizing the use of "dirt" onstage, he did not do it by walking onstage and calmly enunciating, "shit, piss, fuck, cunt, cocksucker mother-fucker and tits."

He dug down into the human psyche, and dirty words were only part of the dirt that he brought up. He turned up basic fears and prejudices that civilized people have learned to ignore. In any age, that's classified obscene