"In the beginning God created the heavens and the earth." — Genesis 1:1
Here we have the keystone to the edifice of the theistic religions. God created things and is absolutely other than the things created. Judaism, Christianity and Islam are necessarily, unapologetically, and militantly dualistic. This is the great parting of ways between Occident and Orient.
How has it served us? Has it served us? I believe it has. Dualism is fundamental to who we are, and through it we have philosophy, science and technology. Has not the Orient produced the same? Yes, but not to the same degree, and largely as an exercise of this same fundamental dualism, and not of its non-dual religious beliefs. They have made other, more important, contributions. And both have their down-sides.
Dualism and non-dualism represent two interpretive aspects of the human experience, and it would be a mistake, I believe, to dismiss either.
A bit further along in the Genesis myth, God creates man: "Let us make man in our own image." We now understand, correctly I think, that it is more a question of man having created God in his own image, and that image is fundamentally dualistic. Even the one God speaks of itself in the plural: "Let us." To whom does it speak? Itself. Just as we do. The absolutely singular and non-dual is beyond our comprehension. "God" in the first verse quoted is elohim, the plural of el, god. Christianity makes much of this in its argument for the Trinity. What Judaism and Islam make of it, I don't know.
Human consciousness, as it has emerged, is fundamentally dualistic. Self-awareness is made possible because we are able to look at ourselves, and this is possible because we are cut asunder. Ingmar Bergman, in his film Persona, begins with an industrial scene in which two anodes approach each other until a powerful electrical spark leaps from one to the other; this is a vivid metaphor for the self; we are that spark supported by our two-ness.
Then, of course, there is the question of why God would create anything in the first place. Was it bored? In need of a distraction? Christianity tells us that it just wanted to be worshiped. What's the difference? Even pantheistic or monistic religions find it necessary to posit an Ultimate that wanted to see itself; even Oneness required a bit of not-oneness, dualism, in order to be fulfilled; in Hinduism, this is called lila. In the case of these latter, these myths are required because the material world is understood at worst, as evil, and at best, as illusory. In either case, we find dualism.
Philosophical Daoism, because it has neither God, nor creation myth, nor aversion to the material world, takes the totality of Reality as seamless from start to finish. The non-dual embraces the dual.
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