The honor of being chosen President of the New England Society for Vascular Surgery is one of the greatest tributes to my life as a surgeon. I have had the unusual good fortune of having two lives in surgery. Vascular surgery always has been my first love--the combination of intellectual, emotional, and technical challenge, the stuff that always has seemed metaphorically like a climb I made with a medical student and our eldest son many years ago on Mt. I(atahdin's Knife Edge in the misty fog.The title of my essay "Single vision and Newton's sleep" may be cryptic to some and more understandable to others. The quotation comes from a letter written in the form of a poem to Mr. Thomas Butts, Great Marlborough Street in London, dated November 22, 1802, by the great visionary artist and poet William Blake.1 The last six lines of that poem are:Now I a fourfold vision see And a fourfold vision is given to me Tis fourfold in my supreme delight And three fold in soft Beulahs night And twofold Always. May God us keep From Single vision & Newtons sleep* Some explanation is necessary. Blake, according to one of his most ardent modern admirers and interpreters, the contemporary American poet Robert Bly, 2 equated single vision and Newton's sleep *Letters [To Thomas Butts, 22 November 1802], p. 720.