IN A HOUSE on a corner of New York's West Side lives an insecure genius named Tony Schwartz. He stays in that house, which is also his office, which is also his world, most of the time, inventing and producing radio and TV commercials for products and politicians. He also writes articles, speeches and an occasional brilliant book. When Marshall McLuhan was alive, he phoned Tony from Canada every week and the two of them talked about communications in the 20th century and whatever else was on their great big minds.

It has yet to be determined whether Schwartz was a disciple of McLuhan or McLuhan was a disciple of Schwartz. But one thing is certain (as they say on the 6 o'clock news) and that is, Tony Schwartz understands media.

Not just "The Media," that beast that dwells in a dark, dark cave and comes out now and then to munch on Ye Traditional Values or demolish a career, and get roundly jeered by everyone, including the very beings who slave in its service, in the process. No, not that bogeyman. Not that, but MEDIA, which is harder to define, though Schwartz makes a stab at it in his mesmerizingly sensible book, "Media, The Second God," the paperback edition of which has just been published by Doubleday.

"The media are everywhere and nowhere," he writes. "They are a spirit, a disembodied entity occupying no space and all space at the same time." Media are not so much part of the new environment as the new environment itself, and there can't be many people on this earth who comprehend that as well as Tony Schwartz does, or who approach media, and the future, with less fear or loathing.

He is fluent in image language, the language the world lives by, a tireless inventor of new ways to use it, the Obi-wan Kenobe of the media age. He sculpts with sounds, composes with video. No addled fuddy-duddy holed up in academe, he has several functioning companies (one of them called New Sounds) and puts his knowledge to very practical uses, one of them being to help elect politicians he likes. Among those who came to Washington, or came back to Washington, with his help are Rep. Tom Lantos (D-Calif.), reelected last fall, and Sen. Warren Rudman (R-N.H.), on whose successful campaign Schwartz worked in 1980.

He has also worked on campaigns of Rep. Tom Foley (D-Wash.), Sen. Daniel Patrick Moynihan (D-N.Y.) and Rep. Philip R. Sharp (D-Ind.). Recently Schwartz toiled for Edward J. King, running for governor of Massachusetts against Michael S. Dukakis. Dukakis was the victor. Schwartz does not see King's loss as a defeat, however. "He lost, but I won," he says. "Everyone comments about the media up there." Indeed, during the campaign Dukakis fired his media consultant and hired a new one because Schwartz's commercials for King were getting all the attention.

Schwartz has lost other races. Does he keep track of wins and losses? "No, no," he says, annoyed with the question. Does a loss indicate bad use of media? "It's really no indication of anything," Schwartz grouses. This line of inquiry seems to strike him as pesky and beside the point.

It's not political savvy but media savvy that sends politicos flocking to Schwartz; they come to his house, because he won't go to them, like pilgrims seeking a guru on a mountaintop. A page from his guest book during a month or two in the fall of 1976 suggests the range of his allure. It includes the signatures of Teddy Kennedy (and Joan Kennedy), columnist Robert Novak, New York Gov. Hugh Carey, Jimmy Carter, Rep. Peter Rodino, then-senator Harrison Williams and media scholar Edwin Diamond. Sen. Kennedy wrote, "Good to work with you, Tony." Diamond wrote, "A trip with a man with 20/20 vision."

Rudman, one of the few Republicans for whom Schwartz has worked, thinks the world of him. "Tony Schwartz, as much as any man, laid the foundation for modern political advertising," Rudman said yesterday. "I think he is one of the most brilliant, incisive people I've ever met in my life. He is also, in my opinion, extraordinarily ethical. The media he did for us was just first-rate."

Schwartz is a great believer in what he calls "paid media," as opposed to mundane old news coverage, for spreading information in political campaigns, and he doesn't think political commercials corrupt the democratic process or demean issues or any of those other roaring cliche's. He lends, even donates, his expertise to causes as well as candidates. In last year's elections he worked on an abortion referendum in Alaska (a win) and a nuclear-freeze referendum in Maine (a loss).

Michael Pertschuk, the Federal Trade Commission's energetic maverick and a longtime admirer, and friend, of Schwartz's, says Schwartz has given "hundreds of thousands of dollars" worth of time to the commission, free of charge, advising it on media matters. Pertschuk, asked if there's anybody smarter in the ways of media than Schwartz, says, "I certainly don't know of anybody. He's enormously creative. I don't know anyone more analytical of the process in which he's involved. He's so in love, and fascinated by, the processes he deals with." Domain

The building is unimposing, but even the front door is media. It creaks so charismatically that the producer of the "CBS Mystery Theater" on radio asked Schwartz for permission to record the creak for use on the show. Inside that house, Schwartz sits, a man among his media--tape recorders, Qwip machines (for sending scripts by telephone), video recorders, TV sets, earphones, speakerphones and four stories jammed with magnetic tapes of voices, sounds and thoughts. You walk in and it's like visiting the house in "Poltergeist," except that what are flying through the air, invisible and electric, are not ghosts, but ideas. Schwartz, though shy and quiet-spoken as they come, gives off vibrations of an intellect on a perpetual rampage.

"This is my office, workshop, everything," he says. "And our home." His residence adjoins the office; there live his children Anton, 15, and Kayla, 20, and his wife, Reenah, who writes political commercials herself. They have been married since 1959; Schwartz will be 60 this year. He rarely leaves this universe; he has agoraphobia, a fear of leaving the house. Every morning he goes for a swim at 7 o'clock at a nearby gym, and occasionally there will be brief vacations, but that's about it. He even lectures around the country by telephone.

"I don't like traveling as much as I like being places," he says. "I have zero interest in seeing places and great interest in meeting people." So the world he will not go to comes to him, by wire and messenger and through the air. If this were a century earlier, Schwartz might not be an at all productive member of society, but now space, time and distance, can be violated left and right through electronics. Schwartz is a man of his time if there ever was one. It is total immersion.

The room that serves as his main office is cluttered not only with tapes but with political memorabilia, of this campaign or that campaign, and clocks and gadgets of every conception. He is constantly being beeped by one beeper or another, including one he wears on his belt. During a couple hours of conversation, he is interrupted repeatedly by a variety of beeps, and at an appointed hour he hooks up with Bob Landers, a top "voice" on the West Coast, who reads a commercial into the phone and, simultaneously, into a tape recorder sitting next to him in Los Angeles. Schwartz times and directs the commercial by phone and will receive the tape by overnight delivery.

Schwartz tells Landers not to worry if the reading of the script runs longer than 30 seconds because "I can mnemonic it later," by which he means he will, through editing, combine words or eliminate parts of words without changing the perceived content of the commercial or changing the playback speed. This is Schwartz's specialty; he is the wizard of sound and sound overlapping, a technique he pioneered. There are dozens more.

Sitting at one of this tape recorders and playing tapes of various commercials he's made over the years (he has saved everything), Schwartz says, "I've very carefully studied how the brain hears, and I can record with that in mind. We can hear four times as fast as we can talk. So the question is, what do you do with the other time? People associate to it. There are commercials you do where you leave holes for people to fall into, fall in and fill in. Here, I'll show you."

He puts on a tape of Landers reading the sentence "The state governors met with their respective legislatures convening in the capital city." Then he plays a Schwartzed version of the same sentence. The "gisla" in the word "legislatures" has been removed, but the brain hears the complete word anyway. It fills in the missing part. He covers the hole with a cough sound. You could swear you heard the whole thing.

"No. The 'gisla' isn't there. See, I've very carefully studied the difference between evoked recall and learned recall. Everyone in this business is dealing with learned recall. I'm dealing with evoked recall. The difference is, one functions about a million times faster than the other. Watch. You're going to recall something I never told you. If I say five words, you'll think of the sixth at that speed. 'For the rest of your--' 'Life,' you think. But you think of it even before I finish.

"Well, the brain can fill in things. See, words never exist in time. When I say, 'Hello,' by the time I get to the 'o,' the 'hell' is gone. So, you have the ability to record momentary fleeting vibrations, to recall past ones, and to expect future ones if they're similar to patterns you've heard before." In a way, Schwartz uses words like music. He can make them convey, somehow, more than what they literally mean; he is often dealing with words as sounds, and so he goes beyond verbal communication into something much more rarefied.

He says that what he, and others, are working on, consciously or unconsciously, is "the redesign of language."

Schwartz uses modern electronic communication not so much to convey facts and data, for which he feels it isn't particularly well suited anyway, as to evoke emotional responses, create sensory impressions. "I was the first one to do commercials for the Cancer Society dealing with emotions rather than medical facts," he says. "They would want people not to smoke, and then do spots showing how your lungs were affected or this and that. I took a different approach. I showed kids playing in their parents' clothing. You know, the boy and girl dressing up in their parents' wedding clothes up in the attic, and then we have the announcer say, 'Children learn by imitating their parents. Pause.Do you smoke cigarettes?' "

An award-spinning TV ad Schwartz did for Coca-Cola had no words addressed to the viewer at all. And no motion except for beads of dew running down the sides of two frosty-yummy bottles of good old Ice Cold Coke. The soundtrack consisted of the seemingly random voices and sounds of people at play. That was it. "And it won first place in the Cannes Film Festival," says Schwartz, with a somehow humble gloat. "I hear they stood up and applauded." Campaign

The most famous, or infamous, political commercial Tony Schwartz ever did was the 1964 "Daisy" spot for Lyndon Johnson in presidential battle against Barry Goldwater. The ad showed a little girl pulling the petals off a daisy, accompanied by quotations from Chairman Lyndon about peace in a nuclear world. Then we heard a sonorous voice tick off "10-9-8-7-" and so on and, boom, the atom bomb went off, presumably taking with it the little girl and her daisy, too.

Goldwater's name was never mentioned, Schwartz points out now, yet the Goldwater forces screamed bloody murder, or its equivalent, and the commercial was withdrawn after one showing. According to Bill Moyers, now CBS senior analyst and then LBJ's press secretary, there were never plans to show it more than once anyway.

"It accomplished its purpose in one showing. To repeat it would have been pointless," says Moyers. "I remember that the White House switchboard lit up with calls protesting it, and Johnson called me and said, 'Jesus Christ, what in the world happened?' and I said, 'You got your point across, that's what,' and he thought a minute and said, 'Well, I guess we did.' So Johnson was very pleased with it. It had accomplished its purpose."

Moyers says, though, that he is not comfortable with the way the ad accomplished its purpose. "It was good advertising, and bad politics," he says.

Schwartz says the spot was an example of using "shame" as a social tool. Shame worked in pre-electronic cultures "wherever people couldn't get away from their communications environment--a neighborhood, a town, a village. Once people began to flake away, shame didn't work; they could escape. But in recent years, the speed of communication has changed to 186,000 miles a second. So it means that you can reach anyone anywhere in the country in less than a sixtieth of a second. Everyone, everywhere. Which makes shame one of the most powerful means of social control again."

He used it once in a series of radio ads designed to discourage New Yorkers from letting their dogs go poo-poo in the street.

He also used it later when New York's uniformed services threatened to strike and negotiations stalled. The commercial was addressed to Mayor Ed Koch: "Mayor Koch, remember the great job the city policemen did during the transit strike? When our city was in deep financial trouble and the banks refused to buy our bonds? Remember how the uniformed officers bought those bonds with their pension fund money?" And so on. "The immediate reaction when it had hit the air," Schwartz recalls, "was that we got signals from the mayor's office that they wanted those commercials removed as quickly as possible and they wanted to sit down and talk about a settlement."

Until that time, says Schwartz, "no mayor had ever been to negotiations except to announce the conclusion of them," but Koch went to these negotiations personally, and immediately. Result: Strike averted.

Schwartz watches the way other media savants use TV and radio and tends to scoff. For instance, he saw that lavishly produced fizzle-bomb, the Democratic response to President Reagan's State of the Union message, and was appalled. "I call it 'Misunderstanding Media,' " he said the next day. "They were using satellite technology to distribute a prepackaged show. The live reactions of real people on the newscasts that followed it had more emotion and humanity than the entire Democratic response, which showed complete ignorance of media, technology and people."

He has kept an eye on politicians and their media over the years. He says of Ronald Reagan, the great communicator, "The only thing he's doing wrong is the way he's running the government. He's not frightened by the medium. He can take anything he's given and read it well, and so forth. So he's way ahead of the average politician."

Teddy Kennedy shouts too much, says Schwartz, as others have said, but another thing bothers him about Teddy's campaigns: "When he runs a campaign, he gets 20 cooks in. He brings everyone in. He can't just put someone in charge and leave him in charge of everything. I pulled out of one of his campaigns because you do something and then they play it to 20 people. I can't work that way."

Tony Schwartz is, in every conceivable sense of the word, independent.

Schwartz worked on Carter's campaign for reelection during its last weeks. "Generally, I say you can't tell about anyone until you work with them. Carter came in here for, I'd say, a total of five hours. Very efficient, very cold, very detached, no chit-chat or anything. He was very lovely to my son. He was so patient with him and gentle with him. Other than that, the only comments he made in here--he walked over to the 'L' section over there and said, 'Where are your tapes on 'Lust'?

"The person I was most impressed with, as in being in the presence of a great man, strangely, was Ed Muskie. I don't know why. I did about three hours of taping with him, just interviews, and his depth of field was real. You could tell that."

Sen. Rudman says, "Working with Tony is a little like psychoanalysis sometimes. You go through a lot. But it's beneficial for everybody. He really talked to us a great deal, asked us a lot of questions about New Hampshire, so it wasn't just some smart guy from New York telling us what to do." Brian Rosman, executive assistant to Rep. Lantos, says for the last Lantos campaign, "Tony did things with sound that are leaps and bounds beyond what anybody else is doing."

Schwartz, who thinks political commercials are much more informative for the electorate than televised debates are, says, "I've come to the conclusion that a political campaign is a fight conducted in front of the public and that no one wants a dirty fighter, and no one wants a nonfighter. They boo a dirty fighter and they boo a nonfighter. And they applaud a clean fighter and a hard fighter. And it's basically that.

"I think the networks, the nonpaid media coverage, tend to make a game out of the whole situation. Here in New York, where you have a media mountain, with a huge overbalance of nonpaid media in relation to paid media, the focus of the campaign is on the race. You'll find no station will ever call you and have a discussion with you about the campaign without having the opponent there and trying to play one against the other. They will have debates where they will give each one 30 seconds to answer, 'How're you going to deal with the crime problem?' So what happens is you find disinterest in voting, and interest in the race, in 'who's-gonna-win?' So people watch the returns, but they don't vote." Tomorrow

Tony Schwartz has devoted his talents and insights to projects as seemingly trivial as a commercial for baby powder. But with such commercials he broke new ground; this was the first spot, in the '50s, to use an actual child's voice instead of a woman imitating a child, as was always done previously. And he learns something new all the time. Even him. He does not face the future with fear. He does not think the electronic media are draining away our humanity or our brains or our capacity to think and reason and feel. The biggest mistake educators make about television, he says, is fighting it instead of using it.

Print is dying even as you read these words on this page. Some despair about this, and picture decline and fall. But these are redefining times, and things like "literacy" and "knowledge" may have to be among the redefined. In "Media, The Second God," Schwartz writes, "Growing up in a post-literate environment, our children have received a vast store of information about the world we live in without requiring the ability to read and write, a lack that would have condemned them to utter ignorance in a previous age." It's not that people are losing the ability to communicate, only that we are in the process of learning to communicate in new ways, ways that bypass many of the old constraints of print.

Talking with Schwartz isn't like listening to the high-blown theories of someone mad to keep trendy. He doesn't make proclamations; he comes to conclusions, and he keeps asking himself questions. "It's phenomenal," he says, "what's ahead," and there is not a hint of dread in his voice, or in the smile on his face, either. He answers to the sound of a different beeper. When you step through his creaking door, you walk not into the future, but into a bedazzling, heightened present, and for a while, you may be under the lingering impression that these really are fascinating, privileged times in which to live. It's like your brain just took a ride on a roller coaster, and you can't wait to go again.