Prophecy is the most gratuitous form of error.

Eliot’s aphorism treats prediction as a special kind of mistake: unlike errors made in the heat of action or under necessity, prophecy is often volunteered without being required, and so its wrongness is doubly culpable. The line reflects her broader realist sensibility—skeptical of grand forecasts and moral certainties, attentive instead to the complexity of motives and the unpredictability of consequences. It also implies an ethical caution: confident foretelling can mislead others, harden opinions, or excuse present inaction. The remark therefore reads as both epistemological humility (the future resists certainty) and moral critique (don’t offer certainty you cannot warrant).