The state where you lose track of time isn't relaxation — it's total absorption

Psychologist Mihaly Csikszentmihalyi interviewed painters, climbers and surgeons who described losing themselves completely in their work, and named it 'flow'. It shows up when a challenge closely matches your skill: too easy and you're bored, too hard and you're anxious.

— Mihaly Csikszentmihalyi, Flow: The Psychology of Optimal Experience — Harper & Row, 1990
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