Abstract
This paper explores how the purpose of the concept of knowledge affects knowledge ascriptions in natural language. I appeal to the idea that the role of the concept of knowledge is to flag reliable informants, and I use this idea to illuminate and support contextualism about ‘knows’. I argue that practical pressures that arise in an epistemic state of nature provide an explanatory basis for a brand of contextualism that I call ‘practical interests contextualism’. I also answer some questions that contextualism leaves open, particularly why the concept of knowledge is valuable, why the word ‘knows’ exhibits context-variability, and why this term enjoys such widespread use. Finally, I show how my contextualist framework accommodates plausible ideas from two rival views: subject-sensitive invariantism and insensitive invariantism. This provides new support for contextualism and develops this view in a way that improves our understanding of the concept of knowledge.