The quantification of human environments has a history—a relatively short history. This article explores how the notion of quantifiable reality has become naturalized through the privileging of predictive utility as the primary goal of knowledge production. This theme is examined via the invention and application of temperature— how it was sociomaterially constructed and how it is globally restructuring social organization today. Temperature does not exist pervasively throughout all space and time. Physicists may affirm that fluctuations in relative heat are ubiquitous, but as a measurement of these fluctuations, temperature only emerges through arrangements of political and environmental observations. What phenomena do populations deem worthy of observation? How do populations manipulate materials to make such observations? By tracing the origins of thermometry and investigating modern efforts to reconstruct and model ulterior temperatures, I illustrate that temperatures, like other measurements, are cultural artifacts pliable to sociopolitical efforts of control and domination.