William Duncan Silkworth (July 22, 1873 – March 22, 1951) was an American physician and specialist in the treatment of alcoholism.

Aggrieved, Silkworth refused to return for a fourth year as he had already been accepted to Princeton University (then called the College of New Jersey).

During Dr. Silkworth's career, he is estimated to have treated more than 40,000 alcoholics and was regarded as one of the world's leading experts in the field.

Crucially, he described the powerlessness of alcoholism as an obsession of the mind that compels one to drink and an allergy of the body that condemns one to go mad or die.

Dr. Silkworth further observed that alcoholics could recover if they could obtain an essential psychic change brought about with the aid of a "Higher Power.