THE IS A BETTER TIME than most to remember Edward Steichen, the great photographer, born 100 years ago last Sunday. Besides his own exquisite work, Steichen assembled the "Family of Man" exhibit of photographs at New York's Museum of Modern Art in 1955 -- an exhibit consisting of 503 photos of mostly ordinary people from 69 countries, taken by 273 remarkable photographers, amateur and professional. The show's purpose, said Steichen, was to demonstrate that "the art of photography is a dynamic process... explaining man to man." It was also a striking demonstration of the commonality of human life, and implicitly of the fact that the only lines keeping people apart are the lines people draw.

Only the Armory Show of modern paintings in 1913 had the same kind of public impact as the "Family of Man," and the effect of the latter was probably even more complex. Had that show show been conceived in the late 1960s, it would most likely have been regarded as a flower-child exercise; but coming as it did in the ice age of the cold war, it was taken very seriously, as it should have been. Over 9 million came to view the show as it traveled in several countries. Certain photographs, such as that of the joyous flute-player and his companion -- which served as the emblem of the exhibit -- became world famous.

Looking back at that exhibit now, it is odd to think that the child carried by the pregnant Mexican woman, so beautifully pensive in her photograph, is 24 today. The lovers shown cavorting in various scenes in various countries are getting on. The young sassy British working-class girl who sashays like a music-hall floozie to the delight of her giggling friends is now a bit past the sashaying age hereself. Yet the photographs stay still, proving at least one of the things Steichen sought to prove: that art outlasts everything but death.

As for "explaning man to man," that is always a taller order. And there is no pretending that an exhibit of photographs, even a magnificent one, could point the way to peace and tolerance on its own. What the "Family of Man" did do was to present people brimming with life, and so became what Steichen hoped it would be: a show of "faith in man."