Zen is romantic nostalgia. It is the recorded meanderings of a bunch of outcast spiritual hasbeens. A man is carried thru the rapids of a river in a canoe. He doesn't have a paddle. He leans forward to the front of the canoe, to paddle with his hands.
Water pours in, and the canoe spins, unstable.
So he leans back to the back, but the same thing happens. Finally, he sits with perfect stillness in the center of the canoe, and the river carries him safely forward to a quiet place. Zen is from the Chinese, Ch'an, which is in English, pun. A koan is the spiritual equivalent of a pun. A koan makes our use of being visible in the same way that a pun makes our use of language visible.