WHEN THE GREEK bearing gifts is former actress Melina Mercouri, you know you're in for a treat.

What the former actress, now the minister of culture of Greece, has brought us is the loan of 67 of the finest known examples of the human figure in early Greek art. The exhibit, which opens Sunday at the National Gallery's East Building, includes threescore works that never have been seen in this country.

"You've seen them in the textbooks, you've seen them in the art histories, now come see them in the round," says director J. Carter Brown.

Brown said what struck him most forcefully about the exhibit, which embraces the 10th through 5th centuries B.C., "was the reminder that while we tend to think of art as having progressed from representational to abstract, in fact the earliest art was abstract."

What struck another visitor even more forcefully was how the objects demonstrate the truth of the cliche about the universality of art. The 10th-century terracotta centaur that leads off the exhibit would be at home on a shelf of contemporary naive clay figurines from Brazil; 8th-century bronze statuettes found in the Acropolis, Sparta and Olympia bring to mind the independent metalworking traditions of several cultures of subSaharan Africa; and echoes of Egypt and Asia run through the intervening centuries right up to the beginning of the classical era.

Although few and often fragmentary, the superbly mounted works show the growth of skill and confidence as Greece emerged from the dark ages following the Mycenaean collapse and grew from a scattering of quarrelsome tribes into the founders of Western culture. The earliest figures are tentative, stiff, perfunctory. Gradually the works take on humanity, then individuality and personality. And at last they become Greek. THE HUMAN FIGURE IN EARLY GREEK ART -- This Sunday through June 12 in the East Building, National Gallery of Art.