According to the Taoist School, human and nature are unified. A person is a small world, and a cup of tea reflects the sea. Tea ceremony has assimilated this thought. Although tea is only a drink offered by nature, it contains natural law, and people should learn the law through drinking tea. Tea is the cream of nature, and people can learn about natural changes through brewing and drinking tea, Lu Yu regarded the process of making, brewing and drinking tea as an art reflecting natural beauty. When the ancients brewed tea, they ground tea cakes,,or the. newly picked and baked tea first, then sifted it through a fire sieve, and put the most even and tender powder into a boiler. It would change wonderfully when the water boiled, and the water and tea blended with each other. People could appreciate natural beauty through observing the change. Lu Yu vividly described the tea dust which was just put into the boiler "as floating date flowers in an annular pond," or "as the newly-grown green duckweed on a winding pond or islet." Lu Yu also described the foam, the cream of tea, vividly: they were "as white as snow covert". Tea connoisseurs regarded tea as the cleanest and most beautiful thing in nature, so people should integrate themselves with nature while drinking it. Lu Quan, poet in the Tang Dynasty, known as the Tea Submaster, felt as if misty rain and cool breezes were spraying on him, and the whole world was incomparably bright and clear when he drank tea. When he drank seven cups of tea, he felt as graceful as a fairy. Su Shi, a great writer of the Song Dynasty, liked to row a small boat, draw water from the river, and brew tea in the rural outskirts of a town, or by the river bank. He believed that by doing so, he invited the bright moon and its silver flame into his jar. Chinese tea connoisseurs believed that people should not only demand from nature, they should also care for and understand it, and treat it kindly so that they could live quietly and happily. There is much profound Taoist philosophy in a cup of tea.