Impact, theory of change, and the horizons of scientific practice.

Demands for research to generate impact, along with proliferating institutional regimes for evaluating impact, are a ubiquitous aspect of contemporary scientific practice. Based on participant observation at an agro-environmental research institute in southwest China, this article explores three iterations of a tool for planning and evaluating impactful science called 'theory of change' (TOC). Despite their ostensible common grounding in TOC, I show how an impact scientist's framework, a donor's monitoring and evaluation regime, and a communication consultant's branding strategy each suggest very different normative structures for scientific practice. These structures entail: particular horizons towards which scientific research is to be practiced, precise points in time at which the future effects of research are to be anticipated, and specific assumptions about how scientists' agency should play out across time. Taking the peculiar sensibilities of TOC as a comparative framework, I illuminate IFF scientists' implicit imaginations of how contemporary science does and should generate effects in the world.