Research on nonliterate societies reveals striking examples of “amnesia”: Prior events or beliefs that contradict current ideas and values are either erased from the collective memory or altered so as to be consistent with present understandings (Goody & Watt, 1968; Henige, 1980; Ong, 1982; Packard, 1980). For example, when the British arrived in Ghana in the early part of this century, they found that the state of Gonja was divided into seven territories, each ruled by its own chief (Goody & Watt, 1968). When British authorities asked them to explain their system, the Gonja revealed that the founder of their state, Ndewura Jakpa, had fathered seven sons. Jakpa divided the land so that each son ruled one territory. The British preserved this account of the history of Gonja in their written records. Shortly after the British arrived, two of the seven states in Gonja disappeared as a result of changes in boundaries. Sixty years later, oral historians again recorded the myths of state. In the updated version, Ndewura Jakpa begot only five sons; the Gonja made no mention of the founders of the two territories that had vanished from the scene. Oral historians have observed similar instances of forgetting or altering inconvenient aspects of the past in many other nonliterate societies (Goody & Watt, 1968).

In literate societies, individuals also revise history, especially in response to changing knowledge and political regimes (Greenwald, 1980). People interpret the past in terms of the present and therefore “every generation rewrites its history” (Mead, 1929/1964, p. 351). Because the earlier records are often preserved, people may notice differences between current and previous accounts of the past (Goody & Watt, 1968; Ong, 1982).