About many events from ancient history, we are informed by more than one source. If they are independent of each other, like the accounts of the Maccabean Revolt in the two books of Maccabees, we can rely upon them as two independent witnesses. We can try to explain the discrepancies, and we can, as a rule of the thumb, assume we’re on firm ground when they are in agreement.
The problem is that we must first establish that sources are indeed independent. We cannot solve the contradiction between the two books of Maccabees by referring to Flavius Josephus’ treatment of the Maccabean Revolt, because it is based on 1 Maccabees. This source can, therefore, be ignored. This is called the “elimination of sources”. The principle was described for the first time by the Italian Renaissance scholar Angelo Poliziano (1454-1494), who also developed the “elimination of manuscripts”.