無因 wúyīn without reason Origin Definitions Defs Strokes Stroke Words Sentences Sents 无因论 wúyīnlùn accidentalism the philosophical theory that events happen by chance without a specific cause空穴来风未必无因 kōngxuéláifēngwèibìwúyīn no smoke without fire (idiom) a wind does not come from an empty cave without reason; there is no smoke without fire