The principal focus of the Xin-Xin Ming is the experience of non-duality. It is the home of the famous words: All is One; One is All. There is so much here upon which to feed, and there is much to be gained in doing so. But we are also exhorted to go beyond any and all conceptualization of Oneness: "Although all dualities arise from this One, do not attach to ideas of even this One." (Richard B. Clarke; throughout unless otherwise indicated) "When such dualities cease to exist, Oneness itself cannot exist". The reason for this is obvious: "Don't waste your time in arguments and discussion attempting to grasp the ungraspable."
Non-duality is not a concept, but an experience. It is transcendence of the discriminating mind, the source of all dualities.
I have not had this experience. If that puts you off my verbal kibble, you might wish to move on to another bowl. Only I would remind you that even Seng-Ts'an, though he presumably did have this experience, can also only offer you words, though obviously with infinitely greater authority. Yet even authoritative words cannot give one the experience.
Non-duality is suggested to us as that which transcends mutually arising opposites. The given examples of these are many: liking/disliking, loving/hating, grasping/rejecting, activity/rest, right/wrong, true/false, subject/object, self/other, gain/loss, small/large, and yes, enlightenment/delusion.
All these normal human cognitive activities are opportunities to realize the possibility of another way. I envision the mind as an "unsinkable" Titanic breaking upon these bergs. In this sense, they are like koans. Seng-Ts'an no doubt saw the experience as principally arising out of meditative practice, yet he also thought it helpful to point out the barriers which present themselves in this, our cognitive sea.
Is it with a sense of irony that he writes his first verse? "The Great Way is not difficult for those not attached to preferences." It's as easy as pie for those who have managed that which is the most difficult thing of all.
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