Dr. A. A. Dinwiddie, D.M.(7th), D.Thau., B.Occ., M.Coll., was a Seventh-Level wizard who was employed at the Unseen University as Bursar, succeeding the deceased Mr. Spelter. He expected to spend the rest of his life quietly adding up rows of figures. Unfortunately, shortly after he became the Bursar, Mustrum Ridcully was appointed Archchancellor. The brashness of Ridcully's personality wore away at the Bursar, and Dr. Dinwiddie became almost completely insane.