PEOPLE ARE having a hard time getting a handle on the '70s. That's because there are no '70s. Every decade may be to some extent a reprise of previous decades, but that's all the '70s are; they're a rerun. They not only signify nothing, they are nothing, nothing but a collection of reflections. The '60s are beginning to look positively exotic by comparison.

Television dominated the '50s and the '60s but in the '70s that dominance has lost its dynamism. Today TV has reached a saturation point in both number of TV households and time spent watching by the average viewer. Neither figure is expected to grow significantly any more. TV is Valium-vision now; it's just there, it has nothing left to prove. All network executives have to do is run around making speeches that defend the status quo.

What television has made of the '70s is a spoof. This is the spoof decade. It begs not to be taken seriously, not to be held accountable. Television trumpets, trills and burbles this doctrine nightly.Little of prime-time programming can be taken seriously - even as comedy - or wants to be. In the New Nihilism, the passive-complacent nihilism of the '70s, the gravest sin is to be uncool. Respect for form is as uncool as one can be. And so "Happy Days" and "Laverne and Shirley" and "Soap" are not comedies that satirize or even characterize anything in particular; they are spoofs of situation, comedies.

When you spoof a spoof you get nothing; you get the impression of an impression. Most of television today registers or, for a lulled national audience, pleasingly fails to register, just that way. "Wonder Woman" is a spoof of spoofs of comic strips and not even a comic strip satire the way, say, "Batman" was. Satire is something that both opens and closes on Saturday night, during the 90 minutes of "Saturday Night Live," and even that exception to the rule frequently indulges in self-parody, as if to say that the satirical slings and arrows aren't meant in earnest. Earnest is uncool.

More and more popular entertainment is about popular entertainment, thus sparing an audience the hint of a direct confrontation with so much as a version of reality. Rock songs are about rock ("That's Rock 'n' Roll") or about the state of being a superstar ("Hotel California"). Movies like "High Anxiety," "The World's Greatest Lover" and "New York, New York" are about movies. Steve Martin, the world's greatest comedian, spends much of his act spoofing the idea of being a comedian. Music is, symptomatically enough, produced on "synthesizers." The '70s were produced on a synthesizer.

And people dancing on "American Bandstand" and "Soul Train" often ape the movements of robots, artificial humans. This is a time in which originals imitate imitations and the real emulates the replica.

It's the clone age. When the outlandishly successful Tom Snyder left the news staff of the NBC-owned station in Los Angeles, a Tom Snyder clone named Paul Moyer was hired to replace him; why risk disrupting a comfortable viewing public? Audiences flock to see mock Elvises and their pelvises or the pseudo-greasers of Sha-Na-Na or the stage smash "Beatlemania" which is "not the Beatles" but "an incredible simulation." And Ford peddles its Granada on television by asking us as we look at the car, "Can you tell it from a $20,000 Mercedes?" Originality is a dead value. Dead dead dead.

In this spirit, citizens of the consumer nation are encouraged by the mass media not to live but a adopt a "lifestyle," with television displaying a variety of lifestyle types which in the long run are all exactly alike. TV tells us life, like television programming, is a modular structure into which various pre-fab components can be inserted for this or that desired effect. There are two conceivable goals. One is to be a "super guy." Lofty aspirations toward truth or beauty are uncool and loonily outer-directed; the gospel according to the est Coast - once the West Coast, and still Hollywood - discourages them nightly on television.

At the same time, characters in TV dramas and comedies have established that, ironically, the highest possible praise one human being may afford another is to apply to him or her the word "special" or, to go one notch up from there, "very special." To be a success in the '70s, according to the theology preached by television, is to be a very special, very together, very super guy or lady. No caricature of this ideal being is possible because it is by design a creature without features; it's the home-grown pod-person of the S-F classic "Invasion of the Body Snatchers" just at the point where the fingerprints have cooled.

Never before has the dominant entertainment medium both been so dominant and provided on demand such passionless diversion. The characters in TV drama slide around on silicone without ever really interacting, unless, of course, they kill each other. In a recent and altogether typical ABC movie, "Doctors' Private Lives," no attempt was made at investing the characters and their alleged love affairs with even the scantiest suggestion of fervor. Again there was implicit accord between program and viewer that none of this was intended to be convincing or disturbing. It has developed that television programs which make viewers feel uncomfortable or threatened - "King" or "Tailgunner Joe" or "The Richard Pryor Show" - are certain to fail.

People get their ideas about how to act in their own lives - how to conduct love affairs, and how to react to pain and death and tragedy - from television. The lesson TV teaches in the '70s is not to react at all. Television is holding up to millions of people every night the idea that the way to get through life with a minimum of scathe is to be as colorless and vacuous as possible; thus does "Rhoda" quickly apologize for any overt displays of emotion on her part. The behavior models in hundreds of TV commercials also practice this preachment - it's the "Nice" Ethic - and from them viewers learn how to order steak-and-Lowenbrau and how to make innocuous toasts with Inglenook, during those "times that are, somehow, just a little special."

Constant exposure to television and the sameness of its programming have not led to mass outbreaks of image exhaustion, media intake overload or demands for change. Au contraire. Exposure to the familiar on television seems only to have induced during the '70s a widespread craving for more of the familiar that may be the most severe such craving in history. Television recycles old formats at an unstoppable rate, from "The Price is Right" to "Name That Tune" to "The $64,000 Question" as "The $128,000 Question" to "One Step Beyond" as "The Next Step Beyond" and commercial after commercial spoofs established forms like movie musicials, melodramas and other commercials.

This creative lethargy is highly contagious. On Broadway now one may choose among such daring novelties and trail-blazers as "On the 20th Century," a musical based on a 40-year-old comedy that was already a movie; Carol Channing returning in "Hello Dolly!"; Yul Brynner returning to half of the title role of "The King and I"; "Beatlemania" with its incredible simulation of The Beatles and "Annie" with its credible simulation of '50s musicals. The longest running show on Broadway is "Grease," a spoof - what else? - of the '50s that by this time has achieved parasitic stasis, the spoof having effectively replaced the object of the spoofing.

One might point to "A Chorus Line" as Broadway's shinning contribution to the theater during the '70s except that, if anything, "Chorus Line" reflects the influence of television; it is a plotless series of modules, like commercials, in which actors talk to the audience (or to an unseen stage director) much as many of the people on television talk to the camera. "A Chorus Line" is Broadway's monument to television's abbreviation of the attention span.

And the most popular movie of the '70s, meanwhile, also the most popular movie of all time, so far, is not so much a motion picture as a motion picture retrospective - "Star Wars," wonderful, exhilarating, dazzling and spectacular and an addition of precisely nothing to the vocabulary or range of the cinema. Indeed, "Star Wars" endorses with the most convincing possible gusto the '70s idea that nothing new is necessary, that to attempt the new is to be, in a way, presumptuous and overly serious. Better to return to the old and spoof it.

This is the '70s TV has wrought - a time in which the concept of originality is a joke that nobody tells. Intentional satire is out; spoofery and a general air of just-kidding is in. "The Gong Show" spoofs the very notion of rewarding talent; it celebrates amateurism and professionalism and bad and good as equals. Now television will be further inevisio," "The Cheap Show," "The $1.98 Beauty Pageant" and the return of "Fernwood 2-Night" as the revised "America 2-Night." In its new form this program will put actual guest stars and parodies of guest stars side by side for a show-business lampoon of show-business hokum; hokesters and hokees will join together as hucksters hawking anti-hucksterism.

How to tell the model from the spoof? In the '70s, it isn't necessary. Any form will accommodate any content; if the form is familiar, the audience will be comfy. Thus it has been found by more than one religious organization that the way to push God is through happy TV talk shows, replete even with an Ed McMahonesque Greek Chorus to echo the stars and cue studio audience response. One such program recently promised "an action-packed week of exciting guests!"

Television has so accustomed us to undemanding and disposable diversion that we expect other types of popular entertainment to be disposable as well. Composers of commercial jingles turn to writing popular songs and the songs become as glib and disposable as commercial jingles. You can tell by how quickly a pop song becomes a jingle. "Feelings" made it to jingledom in record time; its success with the public as a song was just an interim stop on the way to the telephone company, in whose ads it now resides. The same thing will happen with "You Light Up My Life." The electric company will probably buy it.

The charming '60s notion of rebellion against established authority is extinct. TV made it cool and cute. TV transmogrified the rebels of the '60s into series heroes who buck stubborn authorities comically and cutely: "Baretta," "M*A*S*H," "Welcome Back, Kotter," "Black Sheep Squadron" "Starsky and Hutch" and, for next season, two different shows about anti-establishment "street nuns." The whole impulse has been defused. About the only vestige of '60s rebelliousness visible in pop culture is punk rock, but punk, little more than brash trashing anyway, has been a flop as music; its only influence has been on parody fashion.

One looks at TV programming today and one can only ask, CAN THEY BE SERIOUS? Can they possibly be serious in creating and offering "Charlie's Angels" or "The Amazing Spider-Man" or "The Return of Captain Nemo" or "The Incredible Hulk"? Do the actors and producers show up for work and say to each other, "Let's make this great"? The material doesn't even have the integrity of raw pulp. It has only the faint fuzziness of a 12th carbon.

Movie companies respond to America's TV-nurtured mania for the familiar with remakes and more remakes - remakes of "King Kong" and "Hurricane" and "Superman" and "The Big Sleep" and sequels to "Gone With the Wind" and "Casablanca" and, potentially, anything else ever done.

They are even planning a remake of "Invasion of the Body Snatchers." In the original, seeds from outer space drift down to earth and grow into pods which can reproduce whatever life form they are nearest, though not quite completely. If one goes to bed at night with a pod in one's basement, one wakes up the next morning replaced by a soulless, cipher version of oneself.

There's no need to set the remake in the future. They can put it right here in the '70s. Then they won't need to place a pod in anybody's basement.

They can just put a TV set in the living room and turn it on.