People today distinguish ...

People today distinguish between knowledge and action and pursue them separately, believing that one must know before he can act... . They say [they will wait] till they truly know before putting their knowledge into practice. Consequently to the end of their lives, they will never act and also will never know.
 Wang Yangming

Quotes from the same author

The sages do not consider that making no mistakes is a blessing. They believe, rather, that the great virtue of man lies in his ability to correct his mistakes and continually make a new man of himself.
 Wang Yangming
If you really want to find out something about immortality, you have to live in the mountain forests for 30 years. If you succeed in perfecting your eyes and ears there, if you harmonize the heart and the will so that your mind becomes clear and pure and free of all that is evil, you will be able to discuss the matter.
 Wang Yangming
Thought and learning are of small value unless translated into action.
 Wang Yangming