The relationship of the playful and the earnest is an intriguing question in the history of thought from antiquity to the present. Most of the time, those terms are taken to designate dispositions of spirit that are mutually exclusive ones, defining the two poles of a spectrum of attitudes, which may color our ways of being and doing but must never commingle. Symptomatically enough, the Oxford English Dictionary defines the word “earnest” (in its nominative form) as “Seriousness, serious intention, as opposed to jest or play,” clearly excluding it from any ludic vocation. Two features of that distinction might be noted in a preliminary manner. First, like many binary oppositions, it is characteristically advanced as being isotopical and balanced, yet closer inspection often reveals it to be hierarchical and top-heavy, insofar as the “earnest” is invested with meaning, importance, and value, while the “playful” is relegated to the domain of the trivial, the otiose, the supplementary. Second, many meditations on what might be called the “play concept” founder on the shoals of the earnest; that is, while they take considerable pains to persuade us of their own seriousness of purpose, the radical character of that opposition leads them to logical obstacles that prove very difficult to negotiate. Some of those meditations evince moreover a longing for another kind of thought, one in which play and seriousness converse more fluently. In short, the relationship of the playful and the earnest is a significantly vexed question, and like many vexed questions, it testifies to a persistent cultural malaise. In this essay I reflect upon that question, approaching it from three angles in an effort to determine what shapes it might assume. First, I examine the way it animates—and, at certain key points, distresses—the arguments of three powerful, influential, contemporary thinkers who have turned their attention toward the play concept. Second, I invoke three recent examples of literary practice wherein play and earnestness engage each other in productive, mutually illuminative ways. Finally, I offer some addenda, drawing upon my own experience as a critic, a teacher, and a reader.