Yukio Mishima’s Spring Snow is the first novel in his masterful tetralogy, The Sea of Fertility. Here we meet Shigekuni Honda, who narrates this epic tale of what he believes are the successive reincarnations of his friend, Kiyoaki Matsugae.   It is 1912 in Tokyo, and the hermetic world of the ancient aristocracy is being breached for the first time by outsiders — rich provincial families unburdened by tradition, whose money and vitality make them formidable contenders for so