What does Heidegger mean by “curiosity” and why does he characterize it as a kind of epistemic vice, when most contemporary accounts view it as a virtue? Being and Time disparagingly notes that curiosity “concerns itself with a kind of knowing, but just in order to have known” (BT 217/172); the curious person busies herself with “entertaining ‘incidentals’” (BT 358/310). Building on previous work – wherein I argue that virtues are best understood as tendencies to cope well with existential obstacles to flourishing (McMullin 2019) – I show that curiosity as Heidegger frames it is an epistemically vicious misunderstanding of self and world arising in large part from our tendencies toward impatience, arrogance, and fear. Because Heidegger’s account of curiosity in Being and Time is not well-developed, we will look at nearby texts to get a better understanding of this sometimes-overlooked concept in Heidegger’s corpus.