What phrase does Gregory House repeatedly use about patients in House M.D.?

Gregory House repeatedly says, “Everybody lies,” in House M.D.

The phrase expresses House’s belief that patients may hide, forget, misunderstand, or deliberately alter information about their symptoms and behavior. Because diagnosis depends on an accurate history, House treats every account as evidence that must be tested rather than accepted automatically.

The maxim is one of the show’s signature lines and is closely associated with its case-solving format. House often uses it to justify investigating a patient’s home, relationships, habits, or medical records when the stated history does not explain the symptoms.

The phrase is also the title of the first-season finale, “Everybody Lies.” It is not the title of the series finale, which is “Everybody Dies.” The similar wording of those two titles is a frequent source of confusion.