Fifty years ago is a lot of yesterdays, and Bob Cousy likes to define himself, in part, as “not really a yesterday guy.’’ The great Celtics point guard repeated those words once more last week, speaking by phone from his winter home in Florida, and then he added, “But . . . ’’

But on March 17, 1963, exactly a half-century ago, the great Cooz stood on the original, bumpy parquet floor of the Boston Garden and said goodbye. At the event, soon to be dubbed “The Boston Tear Party,’’ a weeping 34-year-old Cousy read from handwritten remarks, his vocal cords slowly tightening, his voice choked to a whisper, and for one brief moment Cousy and the sellout Garden crowd lapsed into almost pin-drop silence.