Focusing on the Middle English poem, Pearl (with evidence from other literary works), this essay considers how the initial situation of the Dreamer explores a half-dozen principles for literary invention that are distinctively medieval, including personal displacement and feelings of anxiety, bewilderment and marvelling. These qualities define the initial state of mind which enables the Dreamer’s visions to occur and develop. Aristotle wrote in his Metaphysics (I. 2) that philosophising begins with wondering and questioning, a principle revered throughout the Middle Ages. Though all these elements of what we now call ‘creativity’ have their roots in practices of invention and argumentation described in ancient philosophy and rhetoric, the particular shapes that these classical principles assume by the late Middle Ages derive from long-established traditions of monastic meditation and contemplative envisioning more than from academic rhetoric and logic. Bonaventure’s opening to his Itinerarium mentis ad Deum recounts the marvel of Francis of Assisi’s seraphic vision, adapting it as a general method for meditation; Chaucer’s Squire’s Tale turns the marvels of the flying horse and visionary mirror into problems in optics and engineering. Pearl turns the dreamer’s initial wondering within a brilliant fantasy to the means for understanding his own human condition.