Your heart is who you most fundamentally are. It is the groundless ground from which your conscious mind and egoic identity arise. It is no thing — no essence, no spark, no kernel, no chip off the block. It is not a soul or a spirit. It is the tenuous existential arising whose essence is to have no essence at all. It is the suchness of your experience of existence, a groundless ground, a formless form. It is an emptiness. But emptiness is not nothingness. It is a something which is nothing, a nothing that is something. It is, quite simply, mystery. And this is the fundamental you.
There is another 'you', the 'you' you know best, the 'you' of egoic identity, which has declared its independence from emptiness. It sees itself as concrete and real. It has form. It is a soul. It is something — a someone. Thus have we evolved. Thus have we as a species learned to cope with our essential emptiness. Perhaps this was necessary to the survival of the species. Perhaps it was a simple chance adaptation, one realized possibility among many others left untried. How could we know?
This egoic you is not without its problems, however. And these are so apparent, I need not discuss them here. Suffice it to say, it is a castle made of sand built below high water beside an all-consuming sea. And thus we seek another possibility — a return to what is more fundamental within us.
The way of the Hsin-Hsin Ming is trust in heart. It is a return to the fundamental human experience where "my self has not yet begun to exist". Trust is utter surrender. It is not a negotiated understanding between two equal parties, an agreement of mutual respect and benefit. It is the absorption of the imagined into the real. It is becoming what we are, a mere, tenuous becoming.
The experience resultant to this absorption is, I believe, that realization of all-pervading unity common to all the traditions which pursue it. And though many would give it a metaphysical content and attach a name to it, I prefer to say no more than that it is this heart here within.
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