At least three levels of the performativity of economics seem to me to be possible (figure 1. 1). The first, weakest level is what might be called "generic performativity." For an aspect of economics to be performative in this sense means that it is used, not just by academic economists, but in the "real world": by market participants, policy makers, regulators, and so on. Instead of being external to economic processes, the aspect of economics in question is "performed" in the generic sense of being used in those processes.

Donald MacKenzie, An Engine, Not a Camera, loc. 85