At a celebration of his 86th birthday, which was to be two years before his death last week, Buckminster Fuller told of a commitment he made as a young man. He promised "never to use (my) knowledge for personal gain or political power. My life has been, as a result, one miracle after another."

About 15 years ago, I was on hand for a Fullerian miracle. On New York's Lower East Side, a group of youth gangs that had formed the University of the Streets had invited Fuller to speak as a visiting scholar. These were pre-Reagan days, when federal education grants were obtainable by black and Hispanic kids.

A friend and I escorted Fuller to the "campus": an unventilated tenement loft in which the audience, ranging from ex-thugs who had discovered books to former molls who were into Shakespeare. No speaker and audience could have been more mismatched: Fuller, the courtly and cosmic-thinking genius who believed that man remains a technological cave-dweller, and the students whose lives were freighted by ghetto poverty.

The introducer was a tall, thick-chested Puerto Rican student who towered over the short Fuller. Here is the man famous for his dome, he began. He looked down at Fuller's bald head, and the audience, thinking that was the famed dome, laughed, No. no. said the introducer--the geodesic dome.

When Fuller began speaking, he instantly captivated the students. He was fatherly. They were willing sharers of his exuberance. Though he talked of Dymaxions and tetrahedrons as the oils to keep the engines of Spaceship Earth moving through the universe, he let the kids know that he and they were in it together as co-builders of a better neighborhood and a more beautiful, workable planet. Build geodesic domes on top of tenements, he urged. The space is there.

When you are finished with that, join the Puerto Rican and black cultures by building island cities from the Caribbean to the coast of Africa. This idea was a near bliss-out, except that Fuller had brought along an inflated rubber globe that he bounced in his hands like a beach ball. We control this, he said. We can make islands.

The miracle of the evening was in the bonding of Fuller's comprehensive thinking with the specific solutions sought by his audience to its neighborhood problems. His message was that thinking globally and acting locally are not different.

Soon after Fuller's visit, some of the students acted on his inspiration by completing a solar energy unit atop a local building. It cut their electricity bill. In 1968, solar energy on the lower East Side was only slightly less improbable than the creation of new islands to Africa.

Bucky Fuller called himself an "engineer, inventor, mathematician, architect, cartographer, philosopher, poet, cosmogonist, comprehensive designer and choreographer." He left out futurist. Perhaps he thought his writing in more than 25 books and lectures for five decades was an overload the country couldn't manage. Why add the extra weight of his ideas about the future? But that is where he lived, in a state of mind trying to recapture the future before it passed us by unused.

"Humanity has developed a great many badly conditioned reflexes," he said." One is the idea that technology is something new. (We've come to) think of technology only where we began to be the inventors--as machinery of war, or to exploit humanity. I find this anti-technology ignorance very greatly troubling. I say our whole escape (for the future) is through technology."

None of that made Fuller either a materialist or a scientist ignorant of religion. "What of our own experience," he asked, "provides experimental evidence of a greater intellect operating on our universe than the human one? Personally, I am overwhelmed by the spiritual evidence of a greater intellect. Call it God, but a word is just a direction and so utterly inadequate to capture the meaning of this 100 percent efficient, eternal unlimited integrity."

A few years ago, I was at a friend's house in Washington when Fuller came by to share his latest thoughts. For nearly three hours, he was in a trancelike state, as though a natural mystic. He spoke in whole pages, not sentences. He ranged from ideas about the mysteries of God to laments about the unseized opportunities of man. As in the Lower East Side, Fuller came to say that he had surprises. The joy of his life was to let us in on them. It brought joy to our lives, too.