On Kawara, the subject of a vast and elegant retrospective at the Guggenheim Museum, was born in Japan and lived very, very quietly in Manhattan for fifty years until his death, last June, at the age of eighty-one—or, rather, the age of twenty-nine thousand seven hundred and seventy-one days, by the form of reckoning that he preferred. Starting in 1966, he created nearly three thousand acrylic paintings, which feature only the dates on which they were made: the month, day, and year meticulously inscribed in white on layered grounds of red, blue, or dark gray. The “Date Paintings” are all rendered in the same sans serif-style, without the aid of stencils, and are horizontally oriented. They come in eight sizes: the smallest measure eight by ten inches, the largest sixty-one by eighty-nine inches. If Kawara couldn’t finish a day’s painting by midnight, he destroyed it. It was hard work. He missed on many occasions, but managed a marathon stretch of three straight months in 1970.