In an era when zillionaires strut their hipness, and boost their investment portfolio, by snapping up the latest follies of Jeff Koons, Tracey Emin, or Maurizio Cattelan, it’s good to be reminded that vast wealth is not always synonymous with bad taste.

Consider the case of Paul Mellon (1907–1999), whose visionary philanthropy is now being commemorated by Washington’s National Gallery.

“In Celebration of Paul Mellon” features eighty-eight dazzling drawings, watercolors, prints, and books (mostly nineteenth- and twentieth-century French, British, and American) in observance of the museum’s seventy-fifth anniversary.1

The National G ...