I read the first 40 pages of The Tao of Zen today.

• "When twelve hundred years of Buddhist accretions are removed from Zen, it is revealed to be a direct evolution of the spirit and philosophy of Taoism." (p. xiii)
• "The spirit of Zen is about naturalness, spontaneity, and inner freedom. But the centuries of company that Zen has kept with Buddhism in both China and Japan have created a formal practice that is stiff, austere, and monastic, qualities that are the antithesis of Zen's essential organic identity." (p. xiv)
• Grigg makes a clear distinction between "religious Buddhism" and "philosophical Buddhism". I wonder how well this distinction is accepted by others, either buddhists or non-buddhists.
• Grigg also appears to make a similiar distinction with Taoism, separating out the philosophy from the various religous sects of Taoism. Thus I think Grigg is going to attempt to remove the philosophical underpinings of both Taoism and Buddhism from their religous trappings and history, and then to compare these philosophies, finding them to be very similar.
• Taoism is based on two seminal Chinese writings, called the Lao Tzu and the Chuang Tzu.

Here are the opening few sentences from Part I Taoism and Zen: The Historical Connections.

• As the consciousness of the early Chinese moved from superstitious defensiveness to volitional empowerment, what Arthur Waley refers to as the evolution from a "pre-moral" to a "moral" culture, people began to realize that direct action was more effective than religious ritual in influencing events.
  In early China this option of personal assertion as a response to unfolding circumstances first appeared in The Book of Changes , the I Ching. Its essential subject was the interplay between a constantly changing world and a self-concious individual who was seeking options within these shifting circumstances. (p. 3).

This isn't a bad description of life on earth in the year 2000.

When I returned from Beijing a couple of years ago, I bought a book on Chinese history which I have yet to read. It is called "A History of Chinese Civilization (2nd ed.) by Jacques Gernet (1972). I will attempt to cross reference some of what Grigg says with this book.