I find it helpful to distinguish between at least six meanings for the word dao. For the most part, these meanings are not based on a scholarly understanding of the evolution of the term within Chinese philosophy, but upon a personal response to Daoism generally.
The first meaning is metaphysical. Dao in this sense stands for the Ultimate. Though suggested as necessary, this Reality is utter Mystery and remains for us entirely inaccessible and ungraspable. It is not understood as acting in the world, though all action, as well as all else, is Dao. Dao is not only in all things, as Zhuangzi suggests, but is all things. Metaphysical Dao is a vastness toward and into which we open ourselves as to Mystery without objectifying it.
The consequence of this openness is Dao as a point of view. This is the second meaning of Dao. "The view from Dao" is Dao. Dao in this sense is a way of being in the world. Among the attributes of such a point of view is an all-embracing and all-affirming equanimity toward all things and events. It is a freedom from fear and prejudice which allows one to wander at ease in the world. It is this that is the philosophical Daoist's highest vision; metaphysical Dao takes care of itself.
The third meaning of Dao is of a course of study, a philosophy by which to realize the mind of Dao. The way of Zhuangzi is such a Dao. There are many others as effective if not perhaps more so. Ziporyn consistently translates Dao as "Course", and it is this meaning that he has in mind. I find this problematical simply because it fails to convey the other meanings.
Fourthly, I suggest that Dao speaks of that 'spiritual' way unique to each one of us. Whatever general way, Daoist, Zen or other, that we choose as our springboard, our own responses to it will necessarily be our own and individualized. We all have our own Dao.
Fifthly, there is that Dao which is the natural expression of each thing being itself. This Dao is unchosen and unavoidable since however each one expresses itself is an expression of itself. There is the Dao of trees and the Dao of this particular tree.
Finally, there is the Dao of the art of doing something well, of doing something so skillfully as to go beyond skill. This Dao, too, can be a practice and point of entry into the mind of Dao.
All these meanings appear within the texts of Daoism and seldom is there any reason for our confusion unless we insist there only be one usage.
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