Flow sounds appealing, and it seems to frequently coincide with some of our most pleasurable pinnacles of human experience, but it doesn’t necessarily translate into optimal performance. In great athletes, performing artists, writers, chess-players, doctors, nurses, air-force pilots and others, beneath the surface of effortless flow is unrelenting determination. And if developing one’s potential is key to a meaningful life – developing what Immanuel Kant speaks of in the Groundwork for the Metaphysics of Morals as our duty to cultivate our ‘predispositions to greater perfection’ – then flow, while bringing momentary happiness, might impede the attainment of that loftier value.