He did leave, and became a force in the world of education in his own right. Over the course of four decades, he served on commissions and boards and held administrative positions at several colleges, including serving as president of Illinois College in Jacksonville, Illinois, and vice president of the American Assembly at Columbia.
Fortunately for Princeton, Bill did heed the other half of his professor's advice: he came back. At the request of Woodrow Wilson School dean Donald Stokes, Bill wrote a history of the Woodrow Wilson School's early years that was published in 1984. And there began the prodigious writing output that Princeton alumni and many other readers continue to enjoy today. After that first book, Bill averaged about one a year. His topics ranged from Isabelle McCosh to Princeton's chapels; from the role of women at Princeton — before coeducation — to Reunions. He wrote the histories of Nassau Hall, Maclean House and Alexander Hall.
Bill's affection and his work for Princeton went well beyond his books. He always said "yes," whether it was to serve on a steering committee or volunteer for a major capital campaign. He was a member of the Alumni Council's Executive Committee and could be seen wearing the trademark DaVinci hat as a P-rade marshal well into his 80s. Quite appropriately, he once served as chair of the Princetoniana Committee.