Fear is not the first feature of educational experience associated with the best-known progressive educational theorists--Jean-Jacques Rousseau, John Dewey, and Paolo Freire. But each of these important thinkers did, in fact, have something substantive to say about how fear functions in the processes of learning and growth. Andrea English and Barbara Stengel juxtapose the ideas of these thinkers in this essay for three purposes: (1) to demonstrate that there is a progressive tradition that accounts for negative emotion in learning; (2) to explore doubt, discomfort, and difficulty as pedagogically useful, with links to fear as both a prompt for and an impediment to growth; and (3) to suggest that teachers take negative affect into account in their pedagogical practice. In doing so, English and Stengel join with contemporary theorists in and out of education to recognize that affect cannot be left out of social theory and that understanding the play of emotion is an integral part of creating truly educational contexts and experiences. The authors' focus here is on fear in processes of learning.