In support of Frans van Lunteren’s project for big-picture history organized around “mediating machines,” these comments stress “mediation” as active agency in the world rather than as mere metaphor, on the view that this active agency underlies the potency of technologies as mediators, both between different domains of knowledge and between theories and things. Similarly important for this power is the diversity of the particular constructions that constitute mediators like “balances” or “engines.” Diversity of meaning and action gives them their cultural reach, from mechanical contrivance to natural process to political ideology. An interesting question remains about how many mediating machines will suffice for the big picture of modernity over four centuries. Statistics, for example, might be a crucial addition. Another question concerns how to characterize the knowledge regime of a mediating machine. Van Lunteren chooses “information” for the computer. He might also have chosen “complexity,” with different import for the character of postmodernity.