Say that Louise Nevelson at 77 is the greatest living sculptor in the United States, and most people who think about such things will agree. Say that Nevelson is the country's greatest living sculpture, and a great many more will say yea, verily.

The evidence: A five-story, 29-ton steel "Sky Tree" Nevelson sculpture has just been mounted at 3 Embarcadero Center, San Francisco. Another major Nevelson work is to be made for the Philip Hart Memorial building, a new Senate office building. She is now completing a commission to the bronze doors of New York's St. Peter's Lutheran Church Chapel. In Washington, Nevelson sculpture can be seen in the Hirshhorn Museum.

Last week she tied with mary Tyler Moore and the Empress Farah Diba of Iran for top honors in the 1976-77 best-dressed women award - the first sculptor to appear on such a list.

"Dawns & Dusks," taped conversations with Nevelson by Diane MacKown - her assistant, her biographer, her Boswell - has just been published by Charles Scribner's Sons, New York. "Louise Nevelson," a book by her art dealer. Arnold B. Glimcher, has just been updaged and published as an E.P. Dutton & Co. paperback.

And Nevelson is now negotiating with an anonymous admirer to turn her house into a Nevelson museum for an amazed posterity. As Nevelson put it the other day, "If someone called and said they were giving me the Versailles Palace, I wouldn't be surprised at all."

As at some other new York places, there is graffiti around the grilled doors on Spring Street; the medium obviously is felt-tip pens.

A young man answers the door and says politely, "She's upstairs. " As you come in the small, cramped, dark, marble-floored foyer, ahead on the stair landing is a typical Nevelson black sculpture. It fits almost wall-to-wall, and ceiling-to-floor, as though it grew there (and it may well spill, spreads out over the wall and up the ceiling.

Here, in this place, the line between sculpture and house is so fuzzy that no one can really say which is which or what is what. There are only two colors - if white and black may be so considered - to be seen as you go up the marble steps and the rather institutional staircase. But finally, at the next landing, there is a rainbow: Louise Nevelson.

In her works Nevelson has only permitted herself to use black, white and the metallics. "Once, many years ago, someone said to me, 'You know you could sell a lot of things if you would put just a little red and green and maybe a bit of yellow there,'" she said. "But I have to do it the way I see it."

She leans over the bannister as her guests come up. When they reach her level, she greets them as though they are long lost lovers returned - though she had never seen either before. SHe looks at people, really sees them, and makes her judgment quickly, by the jewelry and the color a woman wears or the way a man reacts to her costume.

If she likes what she sees, or is amused by you or feels that you are reaching out to her, she will throw herself at you to bridge the chasm between you in a torrent of words, guestures, ideas, concepts, creations, set pieces. You feel as though, for this moment of time, there is nothing so important to this great artist as her need to tell you what her life has really been so that you, you alone, will understand. There is hardly anything so flattering. And so, for that time, those so honored fall under her spell and soak up her words and try to follow with their eyes the dance choreography that is her usual way of moving.

Nevelson has given her self with enthusiasm.She has been high priestess to our era of art. She was president of Artists Equity, an organization bent on helping the artist with a few home comforts like insurance. She has lectured for museum fund-raisers and given parties to raise money for matching grants for composer Merce Cunningham. Recently, she joined in the protest of artists against the French action in freeling Abu Daoud, a suspect in the Munich massacre of the Jewish Olympic stars.

Nevelson is also something to look at. As they say, she is her own best sculpture.Afterward, when you can think about her illusions more dispassionately, you wonder how long it must take her in the moring to put it all together. All those pairs of false eyelashes. How many? Four perhaps? And dark emphasis lines around the eye and eye shadow and dark lipstick and a bit of rouge. Over her thinning gray hair is, today, "a rag. I buy these bits of cloth from the Japanese shops. Maybe 50 cents. They're batik. Pretty." She always wears such a small scarf, or a wig or a remarkable hat, perhaps a jockey-style. She has boxes and boxes of them, all clear plastic boxes, all neatly stacked.

Today she wears an American Indian belt and beads from "Old Guinea, young Guinea, I don't know which.I wear them because Diane gave them to me. I have some jewelry I made for myself, but I didn't feel like putting it on so early."

The shoes, sort of primitive earthshoes, are laced together with thongs. They look like they, too, may have come, from that section of the world. There are bracelets on the left arm, but no rings. The hands don't need any extra expression.

The jacket is from Nepal or Timbuktu, or some place like that. Nevelson doesn't remember and neither does MacKown. With a leg recently broken on the ice, covered in a highly ornamented cast - what would that bring at a gallery? - Macknown is stretched out on a hospital bed (bought by Nevelson from Hammacher Schlemmer).

The dress is a heavy art nouveau patterned silk, in the Grecian mode. "I slept in it, I live in it," she said. "You see we had this party last night. And well, it just was too much trouble to change. I usually do that every year, I put together some things I call my uniform. That way I save lots of time. I don't have to think about what to wear.

"I think style is in everything. I am what you call an atmospheric dresser. Now look, when I meet someone, I want people to enjoy something, not just an old hag. If I am an artist, I want to present the same sort of creativity in my appearance as in my work. I have had good results."

Before too long, she takes her visitors on the grand tour. One whole floor of the house is devoted to her clothes; rather, her costumes. The robes are housed in plain black wardrobes, custom-made but looking rather like standard office stock cabinets. Against another wall are stacks of Japanese chests holding her jewelry, heavy wood and metal pieces made to her own design and actually like maquettes of her sculpture. Some of her son's sculpture/furniture is here. One piece has an arched tunnel: The cat, black of course, crawls through and peers at the company but won't stay to have his picture made.

There are no curtains anywhere, only louvered wood shutters. Now she opens one to show her favorite costume, a rare Chinese robe. "A museum piece. I've had it a long time. You see here on the underside. It had holes. I patched them with that iron-on tape. Yes, the kind the children use on jeans. I never mind when I find something I like if it has holes in it. I mend it. Yes, I suppose it is like one of my collages."

And then she moves to another cabinet. This one has coats. "What do you know, yesterday someone sent me this great knitted coat from Wales, I think it was. And someone else, the same day, it never happened to me before, but these are metaphysical things, we don't understand them all, sent me this macrame cape from the West Coast." Later, on another floor, there is great box, mich decorated and inside a magnificent feather cape. "Howard Lipman saw it, in Tucson and said, 'Louise, you just must have it.'" In the wardrobe room there is another grand piece, a wool suit with cullotte skirt, by a Paris designer. And maybe 1,000 more. "But then I put them all together in many different ways so they seem like even more," she said.

Nevelson doesn't actually sew any of her costumes. "But I pin a lot," she said. "Once on the Ile de France, I took two pieces of cloth and tied one around my neck for a top, and one around my waist for a skirt. 'I'm going to Paris for my fall costume, did you have yours flown over to you?'

"I've always had flair. If I didn't have the money to buy a dress, I could take a sheet and make myself something - dye it a color, put some lace on it and tie it around with a ribbon. When I was young. I bought a frame and put butterfiles on it and made a hat.

"In a way, I suppose I stood in my own way. I didn't convince people I was serious as an artist. It was too good to be true, I know that. I have it, I was bold, but I was really shy. I didn't want any help. Now I had diamond bracelets before I was 20. But it was hard after I left my husband. A lady didn't sue then. You could croak but you couldn't sue. But my family helped me. They bought a house for me, they took care of my son for me so I could study in Europe. I never had any trouble with my family.

"But I think I was out of order for everyday living. Everything seemed too slow to me. It would be hard for anyone to keep up with me. I've always had energy for 20. I asked someone, years later, why didn't you help me when I needed it? And he said, 'How could we do anything for you? You always walked as if you owned New York.'

"I never questioned a part I love it. I haven't indulged myself. but it's like a lady I once knew who left her husband because he had this contract that she was supposed to follow. He said she must make the bed everyday. And she said, 'I am a lady who unmakes beds. I don't know anything about making them."

Nevelson came to the United States from Russia as a small child. Her father, a builder, and mother settled in Rockland, Me. At 20, she married Charles Nevelson, a well-to-do New Yorker. She studied painting and drawing and dance and dranatics. Their only child, Myron, was born in 1922. At 31, she left her son with her parents and went to study with Hans hoffman in Munich, working as an extra in Berlin and Vienna films. She never went back to her husband, but it was 1941 before they were divorced. Her son now is a sculptor too, in Connecticut. "He sells everything he makes. I think he is happy in his work as I am in mine. At first I wasn't happy about it. None of us were selling then, and I thought, no, not another one."

Mike Nevelson has three daughters and a granddaughter, her only great grandchild. "I never thought I was much of a mother. I dragged him up. But what can you do? I did, I must say, give him a great deal of freedom. I wasn't very maternal."

She moved on to what properly would be the living room. There is no furniture there now, only a great and growing maze of black sculptures. "I call it the forest. You see the sculptures are not fastened down, they all can be moved and made into another environment."

In the dining room is another group of sculptures, propped on top of a bank of cabinets which look very much like filing cabinets. There are five rustic tables, each with a drawer, to be pushed together or separated, and woven-fiber Danish chairs.

In the principal room, the party or family or what-have-you room, there is a great round table, bit enough for all King Arthur's men. It's painted black, but brightened with a sterling silver platter and pitcher. There is hot black tea and cheese in case anyone in hungry. The chairs are the plywood and chrome-stacking type, the kind you expect in an auditorium. The other principal furniture includes a narrow, map-type filing cabinet, and MacKown's bed, a temporary fixture, her bedroom is actually upstairs.

Along the bannister, neatly arranged, are paper sacks full of wood shapes cut for her by two assistants in the wood-working shop next door. "I used to have to do it all. I used to paint my things, carry them on my back. Do it all on my own. I don't do it any more. Nature gives you what you need to filfill your life," she said. "I don't even go to the supermarket anymore. Time, uninterrupted time, that's the greatest luxury."

Downstairs is the studio and another kitchen. "I don't like to have just one place to work, " she says, pointing to the folding picnic tables and the bottles of glue. Against the walls, stacked so neatly you could think them a sculptural arrangement, are the plywood panels with the foil and paper collages which will serve as designs for the vestments for the chapel. And against another wall, panel after panel, hundreds of wood collages: Thin pieces of wood, some weathered, some new, pasted to make pictures, sculptures, collages - what can you call them? - all beautiful.

"I think these wood pieces have a life of their own. Years ago, I took a trestle that belonged to the city. A policeman stopped me. He asked what I wanted to sketch it. And he asked where I lived. He said he was going to come and see if I were an artist. I was younger then. I said, 'come along, but don't come empty-handed. Bring a bottle of whisky.' And he did come and he did bring a bottle of whisky. Yes, I guess (being pretty) does help. I never denied what nature did for me. These things are just the geography on the face of the being."

The plaster throughout the house is not that perfect.The architecture is early New York institutional - indeed one of the two houses put together to make one was once a doctor's clinic. But it all has a look of being scrubbed, wiped down, spotless. "I may stop while I'm working four times to sweep. I always know where everything is. Once I took a piece off a sculpture. Your feeling for space, you know, changes. But years later, someone wanted the piece put back. I didn't mind. And I knew right where that piece was, in the midst of 60,000 more."

You realize at last, that is is indeed all illusion. The house is an elaborate stage set, a background for the long-running repertory performance called "one artist in many acts."

But it could't have been that easy in the beginning. She didn't sell a single piece until she was 56 years old, though she had her first one-woman show at 41.

As she says, "The timing now is right for me. You become a reflection of your time. I couldn't do what I do if I hadn't lived now. Frankly my dear, I'm not complaining. The fulfillment is really in yourself. The search is in yourself and through your self.

"It seemed to me I was born knowing what dignity meant. I was curious about life, and I lived it. I liked to smoke and drink. I don't swear as much anymore. I don't want anyone tying me down. I think I have experienced in life many emotions. But I am not about to say goodbye. I have a few other things I want to do."