The Zhouyi (Book of Changes) has its roots in ancient attempts at prognostication, but we need not subscribe to any superstitious hocus-pocus to discover helpful insights within it. What it can provide is a structural means by which to understand the dynamics of change so as to make better informed decisions which do affect our future. According to Ziporyn, the original two lines, the unbroken (Yang/Yes) and the broken (Yin/No), rendered a Yes/No answer to questions posed about the future. "Will my endeavor succeed?" With the combining of these two lines, this developed into a structural representation of the more dynamic character of events. Rather than a straight-forward Yes/No, the answer might be "possibly yes, but" or "possibly no, but."
The first level of combining the lines is in pairs, of which there are four possibilities: Two Yangs is Yes. Two Yins is No. A Yin over a Yang is a Yang-to-Yin transition. A Yang over Yin is a Yin-to-Yang transition. In answer to the question whether my endeavor will succeed, disregarding any attempts to predict the future through the chance occurrence of one of these four, I might instead consider my decision in the light of all four. Success might lead to a larger failure (Yang-to-Yin). I may win the contract, but then my competitors will unite to destroy my company. Or it may not succeed, but this will enable a still greater success (Yin-to-Yang). I may lose the contract, but being uncommitted, be able to obtain a much better one.
We can see then how such a structural representation of the dynamics of transformation can open us up to a more dynamic interface with our being in time. Yet this is, from the Daoist point of view, still largely Yang-ish (seeking to know) if unaccompanied by, and indeed not subsumed under Yin, in this case understood as not-knowing, or more simply, Doubt. We do not know what will happen. We apply our understanding to our decision making to the fullest extent possible — and then "hand it all over to the unavoidable", namely, what actually happens. And whatever happens is ultimately of no great consequence since we have hid the world in the world so that nothing can get lost. This is the value of the non-value Yin, the usefulness of the useless, the empty space (window) that fills the room with light, the hole at the center that makes the wheel work.
There is the old Chinese parable of the farmer who lost his horse and his neighbors who said, Bad fortune! He replied, Who knows? The horse returned with several friends. Good fortune! Who knows? His son was thrown from one and badly injured. Bad fortune! Who knows? The military came to draft new cannon-fodder and his son was passed over. Good fortune! Who knows? And so it goes. This demonstrates the truly unpredictable nature of the unfolding of events and suggests an attitude of non-attachment to any particular outcome. But still the farmer and his neighbors seem to believe that there is 'good' and 'bad' fortune, despite our inability to know which is which. And although philosophical Daoism would concur that such is the case on one level, it also suggests another sense in which there is no such distinction at all. This is the view from Dao.
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