After completing "Next Stop, Greenwich Village," Paul Mazursky said that working on location in New York City had been such a "total high" that he was thinking of moving back. Born in Brooklyn in 1930, Mazursky surmised that it might be more satisfying to divide the year between residence in New York and Los Angeles, where he settled in the early '60s. That move put him in intimate comic touch with the social and emotional confusion depicted in "I Love You, Alice B. Toklas," "Bob & Carol & Ted & Alice," "Alex in Wonderland" and "Blume in Love."

Mazursky's new picture, "An Unmarried Woman" - an exceptionally appealing comedy-drama about the adjustment of a contended housewife and mother, played by Jill Clayburgh, to the sudden, immobilizing dissolution of her marriage - settled the issue. It was shot entirely in New York in the spring of 1977. Mazursky, his wife and their youngest daughter, now 13, moved into a Greenwich Village apartment during the winter. "Two years ago," Mazursky said, "I was thinking along the lines of six months here and six months on the Coast. I'm enjoying myself so much that I've started to think maybe nine-and-three would be even better.

"Having the freedom to live in both places is wonderful, although I suppose it could get confusing. I look upon Los Angeles as a wonderful resort these days. You can get from it what you need. I never put much credence in the myth that equated moving to Hollywood with selling out, whatever that is. You may have to fight a little harder in that environment to keep you equilibrium and sanity, sure, but I'm convinced that most of us end up doing what we're capable of doing, although we may need to make excuses for not achieving what we fantasize doing.

"If the artist operates out of anything but passion, he's already -. None of us really knows what will turn out to be commercial, so if you only want to be commercial and fail at that, what have you got left? There's no legitimate excuse for not trying to function as an artist even in a commercialized art. Finally, all you're left with is your own ideas and passion, anyway. If you're lucky enough to get money to realize that passion, what a wonderful turn of events!

"It's just that you don't see people out there. Or I didn't anyway. In New York there's been almost too much to do. Someone's always having a little cocktail party. In just the last week I've had breakfast with Bernardo Bertolucci, lunch with Max Schell, drinks with Bertrand Tavernier.I suppose they must have passed through Hollywood, but somehow I wouldn't have heard about it. The range of thinks to talk about seems infinitely larger. Out there they only talk about grosses. It's such a curious business that if you're in the right room at the right time at the right party someone might think of you for a job. I suppose many a deal gets consummated at Hollywood parties, but there's only one topic of conversation.

"Over the years I sort of came to the defense of people living in L.A. when they were put down by New Yorkers because I felt they were searching for fulfillment and experimenting with their lives in interesting ways. I think that tendency may have shifted back here. Even the status symbols in Hollywood have a kind of uniformity now. Like the Rolls Royce and the Mercedes-Benz. There are so many of the damn things in Beverly Hills it's a joke. A pick-up truck should be the next status car. A definite cartoon about Hollywood would have someone coming out of a restaurant and telling the parking attendant, 'Mine's the Rolls,' and you see nothing in the lot except Rollses."

New York looks wonderful in "An Unmarried Woman," which opens here Wednesday. Wonderful in a special way: somehow romantic and mellow without sacrificing a gritty reality either. It's as if Mazursky were looking at his old home town through eyes that had grown accustomed to sunnier and more spacious surroundings. New York is still New York, but Mazursky has given it an unusually warm and airy photographic glow.

"I was tired of movies that showed us the cesspool over and over," Mazursky said. "New York is very beautiful in the midst of all the grungy stuff. There's a beauty to the transformation of SoHo that I wanted to capture. That's one of the hopeful changes I was talking about: the idea that an area of the city can get better if a group of individuals has the determination and resources to make it better. I don't want to sound naive about this. I know there's a certain kind of decay that maybe can't be reversed. My old neighborhood in Brownsville and the South Bronx may be too far gone to repair, for example. But the situation isn't entirely hopless, and you do see miracles here and there. Even the decay has its poignance. In some ways New York may affect me like Venice: It's in danger of dying, so there's something tender about it."

Mazursky's new film evidently evolved out of several years of sympathetic observation of and brooding about the predicament of women friends whose marriages had broken up. "One of the problems for women who are suddenly alone," he said, "is that they tend to jump right back into the same mess. You can argue whether it's due to biological need or cultural conditioning, but it seems to happen frequently. I wanted to indicate that this pattern could be resisted. I think most of us have a lot more choice than we believe we do or care to exercise. At the end our heroine is involved with a very attractive man, but like most guys, he's got his work and his priorities are built around that and he's not about to change them.

"She's drawn to him, but she's not so sure of her own role any more. I think her motives are crystal-clear. It's a small revolution, a reluctance to surrender to that subtle imprisonment of the self that happens in all relationships. One can be freer, less of an appendage. I don't envision her going through life manless. She's hesitant, because she's getting in touch with feelings that aren't quite formulated. I think they rarely are in most women in her position, who've always felt secure and haven't had to earn wages or been motivated by strong career drives. They always feel as if they've been on vacation, and now suddenly school is starting again."

The best scenes in the firm sustain an illusion of social and emotional intimacy that seems remarkably touching and true-to-life. According to Mazursky, perfecting a variety of directorial tricks. "I think actors always know they're acting," he said. "Nevertheless, there are always things you can do to approximate the sort of familiarity you find in friends or members of the same family. For example, I deliberately ecnouraged Jill to go places with Lisa Lucas, who was cast as her daughter, so that they'd come into the shooting with a certain rapport. So they palled around a little, went out shopping together, caught a few shows. All very transparent. They saw right through my motives, and I expected them to, but it can still help to realize the relationship you want to see on the screen.

"In rehearsing the domestic scenes between Jill and Michael Murphy as her husband, I insisted that she go through the undressing routines so that we wouldn't have any ga-ga stuff when the cameras began to turn. I want all the potential embarrassment out of the way before we shoot. On the other hand I didn't rehearse Jill's sex scene with Cliff Gorman at all, because this is a totally different situation. This is her first experience with another man after the breakup of her marriage.

"It's strange and unpredicatable. I wanted to keep the cameras back a bit, so it wouldn't inhibit the actors, and I knew I wanted certain bits of business, like Jill in her panties trotting across his loft to turn off the light, because I noticed right away that she had a cute little ass. What I never anticipated was the sort of excitement she brought to the scene when she got back from turning off the light. That was a complete surprise, and all hers. I had nothing to do with it. It came out of some emotional undercurrent I never imagined. I really admired her for it, and Cliff responded just brilliantly to every spontaneous thing she did."

Mazursky chose Clayburgh for the lead in the first place "out of some subjective something-or-other. The script was finished in March of '76, and we started by considering and eliminating the usual roll of superstars, naturally beginning with Streisand and Fonda. Jill already had considerable credit with me. She had tested for the Marsha Mason role in 'Blume in Love' and the Lois Smith role in 'Next Stop, Greenwich Village.' Didn't get the roles, because I didn't think she looked right, but in each case she tested impressively. I screened 'Gable and Lombard,' paying attention just to her; the quality of the movie was immaterial to me. I saw 'Hustling,' then met her for a day and decided the part was hers. I don't know why. Something about her face and her presence, but nothing clearly definable.

"I had more trouble with the Cliff Gorman role. I spent three months agonizing over it.For a while I was hung up on the idea of using a real sculptor in the role, getting someone from the art world to play himself. Finally, I said to myself, 'Schmuck! You need a street kid.'

"I even thought of playing the role myself. No one will write a decent role for me. I'm still a frustrated actor. I wrote myself another little part in the film, another of my guys named Hal. I'm dying to do something more substantial. I think I'm ready for that sort of challenge.Woody can write leading roles for himself, but I can't do it. Hey, before I go, I've gotta tell you this one: a great line from Woody. He's finished his new movie, you know, the 100 percent all-serious drama, no laughs allowed. He says to me, "This movie is so serious I may have to add subtitles.'"