“So the most difficult thing is always to keep your beginner’s mind.  There is no need to have a deep understanding of Zen.  Even though you read much Zen literature, you must read each sentence with a fresh mind.  You should not say, ‘I know what Zen is,’ or ‘I have attained enlightenment.’  This is also the real secret of the arts: always be a beginner.  Be very very careful about this point.  If you start to practice zazen, you will begin to appreciate your beginner’s mind.  It is the secret of Zen practice.”
— Shunryu Suzuki, in the prologue to Zen Mind, Beginner’s Mind.