Interpolation

Interpolation describes the insertion of words, phrases, or longer sections into a text after it was first composed. Such additions can occur intentionally or unintentionally during copying, editing, or transmission. Interpolations may reflect later interpretation, explanation, or harmonization with other traditions. They are often detected by shifts in vocabulary, tone, or argument, or by disruption of the surrounding context. Identifying interpolation helps explain textual variation and how writings developed as they were copied and reused over time.