In the beginning was his "quixotic vision," as Warren Robbins, the founder of the original Museum of African Art, described the project that started in a row of Capitol Hill town houses.

"I envisioned a museum that would be a rich, fitting resource," he told the 200 guests who gathered last night at a black-tie dinner on the Grand Concourse of the new complex of Smithsonian museums. The cause for celebration was the opening of the spectacular new building and collection that is now the National Museum of African Art.

"And here we see it before us," Robbins said. "Or behind us. Or below us."

And with that, he saluted the unusual architecture that has created a lofty layering of airy levels and spiral staircases, most of it underground -- something you completely forget once inside the museum.

But the biggest achievement saluted last night was the very existence, on the Mall, of this museum -- one dedicated to African art, the historically "nonrecognized, nonvalued, nonunderstood cultural antecedent of that one-tenth of America's multiethnic population," said Robbins.

There was much talk of the lack of understanding and recognition of what museum officials technically call sub-Saharan African art and its influence on modern art.

Smithsonian Secretary Robert McC. Adams invoked W.E.B. DuBois and Picasso ("What Picasso saw in African art was what he called the right to the arbitrary ...") in his remarks.

"For me, to view African art is to awaken to our own constraints of imagination and perception," Adams said. "Thus, I am representative of the need for the Smithsonian's own objective with this museum -- to draw the public's sensibilities into new realms."

And some museum professionals are expecting the locale alone will do a lot of that. "Almost by accident," said Chief Curator Philip Ravenhill. "Maybe a million people will come through our museum who haven't even thought about African art and will find it interesting. That's what I'm waiting for."

The museum that was feted last night is dramatically different from the one Robbins started. Directed by Sylvia Williams for the past four years, the museum is focused more toward study and exhibition, and its collection is more esthetically refined. But Robbins (now a senior scholar at the museum) got a standing ovation after his remarks and was moved to say at one point, "There is no one here tonight who could possibly be as happy as I am to see this vision coming to reality."

And later as guests left dinner, former Smithsonian secretary S. Dillon Ripley stopped for a long chat with Robbins and said, "We wouldn't have it if it wasn't for you, let's face it."

Dinner guests were largely Smithsonian officials and donors and lenders -- some of whom went to great lengths to attend.

Comte Badouin deGrunne, a Belgian collector of African art who has lent some pieces, flew in for the dinner. He began collecting about 25 years ago when he saw pieces that friends had collected. "I saw them in an exhibition and I fell in love with African art," he said. "And with African women as well," he said, laughing.

Collector Franc oise Propper, who lent two pieces, flew in from Paris. "The Smithsonian is known around the world," said Propper, whose collection at home includes Picassos arranged next to Ibo statues. "It's important that African art comes to this museum."

Former ambassador Donald McHenry, now a professor of international affairs and diplomacy at Georgetown University, has some of his own African art as well. "I have on occasion collected a piece or two," he said, looking around the exhibits and chuckling, "but nothing like this."

After dinner there was a reception for 500, and guests wandered the galleries, serenaded by the music of an Ethiopian group of wind and string players called Yared. John Reinhardt, former acting director of the museum, predicted that the museum will have a "revolutionary effect" on people's perspectives of African art.

And from another Washington story, there was Arthur Liman, chief Senate counsel for the House-Senate committee investigating the Iran-contra affair. Last night his role was that of escort to his wife Ellen, who is active on New York City arts boards. "We've been working day and night getting our report out, and this is her night," he said. Liman estimates he will only be in Washington about three more weeks.

"You know, Washington is a beautiful city," Liman said. "I have had enough now.