What resources can literature from the past and present offer when confronting the urgent reality of climate change? What function might the humanities classroom serve when the future of human life seems increasingly precarious? This paper grapples with these questions by taking up Wai Chee Dimock’s recent wager—that literary study in the twenty-first century demands “a trial-and-error experimental method” that she calls climate pragmatism. Cued by this phrase, this paper begins by connecting William James’s pragmatist methods to his own literary pedagogy. It focuses in particular on how James frames passages of literature in the terms of conversion—as sites powerfully charged with the potential to convert passive belief into interventionist action. It then survey several contemporary Anglo-American authors, including Zadie Smith, Lauren Groff, Jenny Offill, and Tommy Pico, whose recent work embodies a turn towards climate activism and exemplifies this model of conversion. As this paper argues, these writers employ Jamesian methods for testing the pedagogical power of art: by staging new kinds of aesthetic encounters, these author-activists seek to educate and incite audiences whose passive belief in the reality of climate change might be mobilized into daily, practical, and substantial—that is, pragmatist—action.