不闻不若闻之，
闻之不若见之，      
见之不若知之，      
知之不若行之；      
学至于行之而止矣    

-- 荀子                                    

Not having heard is not as good as having heard,
having heard is not as good as having seen,
having seen is not as good as mentally knowing,
mentally knowing is not as good as putting into action;
true learning is complete only when action has been put forth

-- Xunzi