Dogen and Soto Zen

Have been slugging my way through a book on Dogen, the founder of the Soto Zen sect in Japanese Buddhism. It is pretty amazing stuff. The way in which he approached the Buddhist teachings and existence were/are revolutionary. I am loathe to try and summarize what the conclusions are, as I feel I would to a poor job, so I will just try and stick to a few minor points that can hopefully be extrapoliated to more practical thought streams.
The thing that is most difficult, and yet interesting, is how his views are based on non-duality among concepts that seem to appear dualisticly (don't know if that is a word, but it is all I got). For example, existence and no-existence, are both important aspects of existence. But, no-existence is not the opposite of existence. It exists independently from existence, and is part of the same whole. A better relationship is the one between Being and non-Being, which is similar to the whole existence thing. Non-Being is not the opposite of Being. It is beyond being, and a reflection of being with everything. The awareness that Being also is non-Being, because you Be so much that you are part of everything. But, the identity of you is going, so you are non-Being as a "you" that lives, you are Being. Once we achieve this awareness and become enlightened are impermanence is understood and embraced. But, you are beyond such concepts as embracing. That is about as far as I can get in explaining a little of the philosophy.
The intriguing thing is in eliminating the duality inherent in the concepts. Things like life and death exist as opposities. Without life, is there not death? Yes, but when you change the nature of how you define the terms, then you can go beyond the conventional. One of the terms used, nonanthropocentric, I think, was intriguing. It means removing Man as the center of a philosophy. If you define Man, or things related to him, as the defining characteristic of your universe, then you are kind of limited in how you are able transcend the ideas about the univerese and beyond. I suppose this is true in all cases. How you define your terms limits how far you can go. So what this post has degraded into is an idea that everyone knows...hmm.
I guess it breaks down to people understanding the terms by which they lead their lives. How do you define what defines you? (That soundd kind of lame) I'll get back to this later.