Historical relativism, or historicism, is the diachronic version of cultural relativism. As Clifford Geertz points out, cultural and historical relativism are in effect the same doctrine with a core claim that “we cannot apprehend another people’s or another period’s imagination neatly, as though it were our own” (1993: 44). Historicism originated in reaction to the universalist tendencies of the Enlightenment but proved most influential in the social sciences, particularly in the hands of 19th century theorists such as Karl Marx and Max Weber. Oswald Spengler, the then-influential turn-of-the-century German historian and philosopher, also declared that: “There are no eternal truths. Every philosophy is an expression of its time” (Spengler 1918: 58). Karl Mannheim, to whom we owe the sub-discipline of sociology of knowledge, pronounced that historicism is a significant intellectual force that epitomizes our worldview (Weltanschauung).