IF EDWARD STONE had designed no building in Washington other than the John F. Kennedy center for the Performing Arts, he still would be regarded as one of the city's important architects. As it is, Mr. Stone also designed the Georgetown University Law School and the National Geographic Building - a work architecturally superior to the Kennedy Center in most ways. But the Kennedy Center was his major effort here, and his major legacy. And the fact of its success as a place for art, if not as a thing of beauty, testifies to how fully Mr. Stone understood this city, and the arts as well.

The Kennedy Center is so much a part of Washington now that it's odd to think back to the late '50s and early '60s when its existence was up for grabs. First the "national cultural center" was to consist of "several 300- to 400-seat rooms," in addition to three enormous main theaters. It was to be 900 feet long, and to cost $50, no $61, no $75 million. There was congressional clamor. Then the price was slashed to $30 million, and the architectural plans reduced accordingly - just in time, of course, for the price to more than double. At one point in 1962 Mr. Stone changed his design to a cluster of separate buildings. To top everything, there was a barrage of 11th-hour attacks on the proposed site of the center. It would overwhelm the city's memorials; it would be inaccessible to those without cars; it would be better located downtown.

Mention those arguments to those who led the attacks in 1964 and 1965, and the hackles rise even now. The most deep-seated worry was not that the cultural center would dwarf the national monuments, but rather that it would become a national monument in itself, and thus not be a place where a fluid culture thrives. Observe the center coldly today, an you understand the concern - which was shared by The Post at the time. There it squats - all 630' x 300' x 100' of it - a short way from the Lincoln Memorial, which it imitates poorly.

Yet Mr. Stone understood what he was doing with the Kennedy Center, perhaps far better than anyone imagined. The building in colossal, but it is also clever. Its size is broken into manageable units for the eye. The grey and white marble on the terrace is patterned in squares and rectangles, so as not to shoot down in one infinite path. The doors are high as well as wide. The trees and fountains flourish in their own compartments. And there's the location itself. No cultural center in the country has a more beautiful view. Nor is there a more pleasant place to stand during intermission or after a performance than on that terrace below which the Potomac miraculously becomes the Thames.

The Kennedy center, is not a beautiful building, but as a place of performance it a beautifully functional one. Mr. Stone did build beautiful buildings - notably the pavilion at the Brussels World's Fair, and New York's Museum of Modern Art - but the beautiful, the special buildings stopped after his famous American embassy in New Delhi (some say just before it), and, like Orson Welles, he became a celebrity at about the same time he set aside the original for ce of his talent. Yet he was always a serious artist. He spoke sincerely of the need to convey "courage" and "dignity" in buildings, and he condemned "the colossal mess we've made of this country" with true rage. As for the Kennedy Center, he undertook the task as a national trust and sought to create a place where on can enjoy the arts wholeheartedly. That he did.