FOR HIS latest big party, Harvey Baskin painted every wall, ceiling and floor in his house black.

The color made a great background for his modern paintings, the two water beds and the Advent super-sized television screen, not to mention his spa bathtub built on a dals, his own glittering crystal sculptures and his staircase rail. The black walls and what goes with them would not be a surprise to the avant-garde, but the appearance is unexpected inside what is a rather staid-looking stone house in a posh section of Washington.

A great many museum and art world people came to the party, and they all loved the house. (The party honored Baskin's sister, Lee Kimche, the new director of the Institute of Museum Studies.) They hailed it as an art object itself - an Environment with a capital E. They said they thought Baskin's decor was dramatic, a splendid foil for his collection of paintings and sculpture, a wonderful space-expander and a nice change after everybody else's house with chaste white walls.

"I liked it too," said Baskin. "The art on the walls stood out. It almost socked you. You didn't notice the color of the walls at all. They sort of receded into the distance."

But another group of friends was upset at the thought - or perhaps the implications - of the all-black walls. A psychiatrist could probably explain why some people were so disturbed. Did they find black walls too dramatic, daring, depressing, diverting - or too dark? Did the black rooms conjure up fantasies of entombment, black magic, caves, dark secrets? Who's to say?

Baskin, after a telephone complaint or two, repainted the downstairs walls white, leaving the ceiling dark. "I gave in because I do conduct business here, and perhaps it wasn't right for business meetings," he said. He stood fast, however, on the upstairs because the black walls were too good a background for the upstairs accouterments.

The upstairs experience starts at the foot of the flying staircase. The railing, handmade by Roger and Jeffery Wilkes, is of clear acrylic posts, smoothly and sensuously rounded. They invite caressing as you walk up the stairs.

At the head of the stairs, you have your choice. To the right is what Baskin calls the entertainment room that includes the Advent screen, a videotape player/recorder, a banquette and a built-in waterbed. At first this was Baskin's bedroom. "But I got tired of sleeping with the M & M's and the peanuts, so I built another bedroom for myself . . ."

Baskin's own bedroom separates from the entertainment area with a sliding wall. He can watch the Advent screen from his bed. And there is a matching stereo. The original wall-to-wall carpeting was taken up and used to cover a built-in platform where a second waterbed sits. The floor is stained black.

Even the bedrooms pale beside Baskin's bathroom (which once was a fourth bedroom). It has a glass-walled shower with six massage jets (only four jet at full force, but his plumber is working on it) and a 3-by-6 foot bathtub with massage jets. The tub is set on a wooden dais and ornamented with a pot of orchids. Baskin's clothes both hang and are drawered in a closet built in the bathroom. The washbasin is in its own built-in cabinet in an open alcove. The toilet is in a closed compartment.

Baskin's office, where he keeps up with his investment projects - "hotels, real estate developments, and so on" - is the fourth room on this floor. "Actually, my office is wherever there's a telephone," he said. "I have a switching device on my phone, which reaches me wherever I am. No one can tell, unless I say just where I am when I answer. I could be here or in California."

The house also is filled with complicated electronic security devices.

The downstairs seems almost conservative after you've seen the upper rooms. All the walls are white, all the ceilings black and the floor is either stained black wood or Pirelli black tile.

The living room has a handsome stone fireplace, revealed after workmen removed layers of plaster and a mirror. "All the inner walls as well as the outer walls in this house are stone," Baskin said. "They're 18 inches thick. The great thing with these old houses is the walls."

Baskin has lengthened all the first floor windows in the house, so they reach to the floor. Some are arched at the top. Currently all the major windows in the house, upstairs and down, have lush potted orchids growing in them.

In the living room is the squishy leather furniture of Atlier International, including sofas, chairs and a chaise selected for Baskin by decorator Gloria Weissberg. In one window of the living room, on a plexi-circle, is a glittering polyagonal Lucite sculpture, one of several Baskin designed to have made by the Wilkes brothers. Several more are on the octagonal coffee table with its plexi base, housemade, as well.

A matching table at bar height stands in the breakfast area. It is revealed when you slide the doors between into their pockets. The kitchen has all-oak cabinets (made on the premises), and the appliances have black fronts. Not one, but two sky-lights illuminate the black.

"In the spring, when the tree above blossoms, it's a riot," Baskin said. Another pot of orchids sits in the kitchen window.

The dining room is somewhat sedate, with Italian furniture. A huge screen dominates one wall.

The large foyer has its Baskin sculpture (also produced by the Wilkes brothers).

Weissberg was with Baskin when he decided to buy the house. He had first rejected it because he thought it looked like a family house - not a bachelor pad. But Weissberg pointed out it could be whatever he wanted.

And today it is. Baskin has decorated the house to suit his own tastes: He painted it all black in three days. "Another time, I had most of the walls downstairs, painted sort of a construction paper color."

During Baskin's two years of renovations, he and Weissberg decided he should go it alone. "I decided to go further with the house than I had intended, and Gloria concluded the time had come for the parting of the ways. Though we are still good friends.

"I really didn't think about the house as a setting for art. I bought all the art, and started producing pieces myself after I moved into the house." said Baskin.

"Since I'm a bachelor, and can afford it, I've been able to rent some rather wonderful houses across the country people have never rented before. So I knew a good bit about what I did and didn't want in a house."

"It just was a matter of giving it my full attention - after my contractor filed for bankruptcy - getting it done. I was lucky to get John Scarmazy to do the cabinets and Nick Promutico to do about everything else. We began by carting out two truck loads of debris. I didn't have too much time to worry about it because it was September and I had to get it all closed in.

"I really think it was just like a business venture. You look around and decide what's your top priority and then you do that."

Baskin lived on the third floor, now being remodeled, while the work was being done. He promises the top floor will be "far greater than anything along the way." But for now, he's going to leave it for a while. "I'm tired of making decisions."