This paper is an investigation of pedagogical tact in terms of vigilance. It is based on a close reading of a passage from Rousseau's "Emile:" a (problematic and troubling) narrative account on the art of hosting a dinner party. Working with the narrative of the dinner party, distinctions are drawn between contrasting ways of knowing, and ways of being vigilant: surveillance and "veillance sur." The paper explores the significance of this twofold vigilance for teaching and for the understanding of pedagogical tact.