Physician.
He and Franklin were the principal founders of the Pennsylvania Hospital, where Thomas and his younger brother Phineas practiced medicine.
Studied with Dr. Alexander Hamilton in Annapolis, Maryland. Completed his medical education in Britain and France.
Practiced in Philadelphia, where he and Phineas were original members of the American Philosophical Society and trustees of the College of Philadelphia.
Began the first course of clinical lectures in the United States (1766).