These words are written on a bright Saturday morning in the spring of 2014, a morning all the brighter because I have just successfully completed a wickedly difficult crossword puzzle dreamed up by Evan Birnholz for the New York Times. Devotees of that newspaper’s puzzles know well that each week’s progression begins with the big, medium-hard Sunday one, then an easy one on Monday, and thereafter marches inexorably to the Saturday toughie.