Economics had developed in the eighteenth and nineteenth centuries predominantly as what the historian of economics Mary Morgan calls a "verbal tradition." Even as late as 1900, "there was relatively little mathematics, statistics, or modeling contained in any economic work" (Morgan 2003, p. 277). Although the use of mathematics and statistics increased in the first half of the twentieth century, economics remained pluralistic.

Donald MacKenzie, An Engine, Not a Camera, loc. 44