According to Azzouni, we know the Gödel sentence as long as we are able to embed the syntactically incomplete system (such as Peano arithmetic) in a stronger system in which the truth predicate for the original system occurs and in which the Gödel sentence is proved (Azzouni 1994, pp. 134–135; Azzouni 2006, p. 89, note 38, last paragraph, and pp. 161–162).