One difference between the approach of Zen and Daoism which I think noteworthy is that the latter spends a great deal more time discussing how the sage comports herself in the world. Zen offers a path to a transformative experience and largely leaves the results unconsidered. Indeed, to dwell on the 'fruits' would be to distract from the 'root'. Daoism, on the other hand, offers little in the way of method, and instead discusses how a sage lives in and responds to the world. It teaches by way of example, Zen by way of method.
The similarities between Daoism and Zen are unmistakable, and this should not surprise us given that the latter (Chan) is a form of Buddhism deeply influenced by Daoism. It is my belief that if there is anything 'real' in either, it is 'real' in both. Only they tend to emphasize different sides of the same coin.
The development of Chan was largely a consequence of the incompatibility of Buddhism and Chinese culture at the time of its arrival. The Chinese were a very practical lot who cared little for ephemeral and escapist ideologies. What is important is living well in this world — living a long, respectful, and honorable life. This requires good governance and the fulfillment of one's obligations in that context, beginning with honoring one's family members according to the position of each.
Thus, the Chinese expression of spirituality as seen in Daoism emphasizes how it is expressed in the world, how it is embodied in the sage. Daoism seems colorful; Chan seems colorless. Daoism emphasizes fullness; Chan emphasizes emptiness. And yet, they are the same in their intended ends.
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