《庄子·内篇·人间世》
听说过凭借翅膀才能飞翔，不曾听说过没有翅膀也能飞翔；听说过有智慧才能了解事物，不曾听说过没有智慧也可以了解事物。
闻以有翼飞者矣，未闻以无翼飞者也；闻以有知知者矣，未闻以无知知者也。
I have heard that you can fly with wings, but I have never heard that you can fly without wings; I have heard that you can understand things with wisdom, but I have never heard that you can understand things without wisdom.