"When such dualities cease to exist / Oneness itself cannot exist. . . . / With a single stroke you are freed from bondage; . . . / To know this Reality directly / is possible only through practicing non-duality. / When you live this non-separation, / all things manifest the One, and nothing is excluded. . . . / Not here, not there— / But everywhere right before your eyes. . . . / Don't waste your time in arguments or discussion / attempting to grasp the ungraspable." (Clarke)
I have condensed a great deal here, so I would recommend you study it in context should you wish to explore it further.
We say 'non-dual' because, as previously stated with reference to Zhuangzi, "One and the saying make two." This is merely semantic, of course, but it does make the point.
The Zen vision of 'enlightenment' is primarily described as 'sudden', as opposed to gradual, although some concessions are often made to a gradual realization leading up to the sudden epiphany.
To experience non-duality, we are told, we must practice non-duality. This leaves us with the chicken/egg dilemma, but that may be the point. Breaking the mind's attachment to cause and effect becomes the breakthrough. Here is a gate.
Oneness means oneness; nothing is excluded. Another gate.
Nowhere in particular; yet in every particular. Another gate.
Realization is experiential; it is not intellectual, nor can it be attained through reason. Arguments and discussions about the nature of reality do not bring us any closer to it. Why do we argue? Should I argue for the non-dual position? Will that make me non-dual? Will it make you non-dual? It is only an idea. Living in the dualistic mind, ideas matter because they help to make me someone, someone 'right' in contrast to some-other 'wrong'. What would it be like to be utterly unconcerned with the opinions of others vis-à-vis my own? Perhaps even those opinions would fall away. And then I would float away; for these opinions are a great burden on my heart.
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