Gandhi isn't simply warning against arrogance—he's identifying a peculiar trap of competence itself, where success breeds the blindness that precedes failure. Notice he calls certainty "unwise" rather than merely "proud," suggesting that overconfidence isn't a character flaw but a practical mistake, like driving with your headlights off. A surgeon confident in her diagnosis might dismiss a patient's unusual symptom; a seasoned executive certain of market trends might miss the disruption gathering at the edges. The medicine Gandhi offers isn't humility for its own sake, but the deliberate habit of remaining uncertain—staying alert, questioning your own conclusions, keeping your mind slightly unsettled.