The Master said, “Learning without thought is labor lost; thought without learning is perilous.” The Master said, “The study of strange doctrines is injurious indeed!” The Master said, “Yu, shall I teach you what knowledge is? When you know a thing, to hold that you know it; and when you do not know a thing, to allow that you do not know it;-this is knowledge.

"Confucius said, "To know that we know what we know, and that we do not know what we do not know, that is true knowledge.

Suppose I try saying something. What way do I have of knowing that if I say I know something I don't really not know it? Or what way do I have of knowing that if I say I don't know something I don't really in fact know it?

lesson about knowledge? When you know a thing, maintain that you know it; and when you do not, acknowledge your ignorance. This is characteristic of knowledge.

When you know a thing, to hold that you know it; and when you do not know a thing, to allow that you do not know it — this is knowledge.

To know what you know and what you do not know, that is true knowledge.

Chao-Chou asked, “What is the Tao?” The master [Nan-ch’üan] replied, “Your ordinary consciousness is the Tao.” “How can one return into accord with it?” “By intending to accord you immediately deviate.” “But without intention, how can one know the Tao?” “The Tao,” said the master, “belongs neither to knowing nor to not knowing. Knowing is false understanding; not knowing is blind ignorance. If you really understand the Tao beyond doubt, it’s like the empty sky. Why drag in right and wrong?”2 [56b]

The Master said, “A true teacher is one who, keeping the past alive, is also able to understand the present.”
(Analects 2.11)

To know that we know what we know, and to know that we do not know what we do not know, that is true knowledge.

"Confucius said,"To know that you don't know is the beginning of knowing.

قل إنك تعرف عندما تعرف، لكن قل إنك لاتعرف عندما لاتعرف.هذه هي المعرفة الحقيقية

When the Master entered the great temple he asked about everything. Someone said, ‘Who will say that this son of the man of Zou knows about ritual? When he enters the temple, he asks about everything’. The Master heard of it and said, ‘This is the ritual’.

The Master said, 'Quietly to store up knowledge in my mind, to learn without flagging, to teach without growing weary, these present me with no difficulties' ... 'It is these things that cause me concern: failure to cultivate virtue, failure to go more deeply into what I have learned, inability, when I am told what is right, to move to where it is, and inability to reform myself when I have defects.

Zen master is not trying to give you ideas about life; he is trying to give you life itself, to make you realize life in and around you, to make you live it instead of being a mere spectator, a mere pedant absorbed in the dry bones of something which the life has long deserted. A symphony is not explained by a mathematical analysis of its notes; the mystery of a woman’s beauty is not revealed by a postmortem dissection; and no one ever understood the wonder of a bird on the wing by stuffing it and putting it in a glass case. To understand these things, you must live and move with them as they are alive. The same is true of the universe: no amount of intellectual analysis will explain it, for philosophy and science can only reveal its mechanism, never its meaning or, as the Chinese say, its Tao. “What is the Tao?” A Zen master answers, “Usual life is the very Tao.” “How does one bring oneself into accord with it?” “If you try to accord with it, you will get away from it.” For to imagine that there is a “you” separate from life which somehow has to accord with life is to fall straight into the trap.