Definition
Ahistoricity is the absence of historical awareness. This has been a challenge of functionalist thought in sociology, which has the predisposition to assume that the society as it now exists is the most significant society that could possibly exist, with little regard for the past and how cultures have evolved into their current condition. Ahistorical is a state of being historically ignorant.
Ahistoricism
Ahistoricism is the absence of interest in the past, historical progression, or tradition. The phrase may also refer to the idea that history has no bearing on or significance in contemporary decision-making. Finally, it may also be used to characterize someone who ignores or fails to place a historical fact or consequence in the context of an argument or problem.