There must first be a True Man before there can be true knowledge. What do I mean by a True Man? The True Man of ancient times did not rebel against want, did not grow proud in plenty, and did not plan his affairs. A man like this could commit an error and not regret it, could meet with success and not make a show. A man like this could climb the high places and not be frightened, could enter the water and not get wet, could enter the fire and not get burned. His knowledge was able to climb all the way up to the Way like this.
The True Man of ancient times slept without dreaming and woke without care; he ate without savoring and his breath came from deep inside. The True Man breathes with his heels; the mass of men breathe with their throats. Crushed and bound down, they gasp out their words as though they were retching. Deep in their passions and desires, they are shallow in the workings of Heaven.
The True Man of ancient times knew nothing of loving life, knew nothing of hating death. He emerged without delight; he went back in without a fuss. He came briskly, he went briskly, and that was all. He didn’t forget where he began; he didn’t try to find out where he would end. He received something and took pleasure in it; he forgot about it and handed it back again. This is what I call not using the mind to repel the Way, not using man to help out Heaven. This is what I call the True Man. …
This was the True Man of old: his bearing was lofty and did not crumble; he appeared to lack but accepted nothing; he was dignified in his correctness but not insistent; he was vast in his emptiness but not ostentatious. Mild and cheerful, he seemed to be happy; reluctant, he could not help doing certain things; annoyed, he let it show in his face; relaxed, he rested in his virtue. Tolerant, he seemed to be part of the world; towering alone, he could be checked by nothing; withdrawn, he seemed to prefer to cut himself off; bemused, he forgot what he was going to say. …
Therefore his liking was one and his not liking was one. His being one was one and his not being one was one. In being one, he was acting as a companion of Heaven. In not being one, he was acting as a companion of man. When man and Heaven do not defeat each other, then we may be said to have the True Man. (6, 大宗師, tr. Watson 1968:77-80)
This excerpt is from Zhuangzi regarding zhenren – The True Man