Dr. Wilson's first name in House M.D. is James.
James Wilson is an oncologist at Princeton-Plainsboro Teaching Hospital and Gregory House's closest friend. Unlike House, Wilson is generally empathetic and diplomatic, although his personal relationships and loyalty to House repeatedly create difficult choices. Their friendship is one of the show's central long-running relationships.
The character is played by Robert Sean Leonard. Wilson's oncology specialty also gives him a distinctive role in the hospital: he treats patients with cancer while frequently becoming involved in House's diagnostic cases and personal crises.
Viewers may remember the surname more readily than the first name because House usually calls him “Wilson.” The character should not be confused with Dr. James Wilson in unrelated medical fiction or with the actor's own name. Within House M.D., James Wilson is the canonical full identity of House's best friend and colleague.