There's no doubt that water is vital to any life. About 60 percent of the average adult human body is made of water. This includes most of your brain, heart, lungs, muscles and skin, and even about 30 percent of your bones. Yet there's little scientific agreement about the exact amount of the stuff an individual should consume each day. So how much water do you actually need to drink to be healthy?

    You may have heard that you should drink eight 8-ounce glasses of water a day. Yet, the downside of this rule, researchers say, is that drinking water by the glass is not the only way that humans take in it. The “8 X 8” rule essentially overlooks two big sources of daily water consumption. One such source is food. Everything you eat contains some water. Watermelons, for example, are more than 90 percent water by weight. Different diets naturally contain different amounts of waters, and the counts. The other key water sources are other beverages. Non-alcoholic drinks such as coffee, and tea, contain mostly water and all contribute to your hydration（水量）.

    So, between all the food, water and other fluids you consume in a day, how much water should you aim to take in?

    The National Academics of Sciences suggests that woman consume a total of approximately 2.7 liters (91 ounces) of warm from all beverages and foods each day and men 3.7 liters (125 ounces). But these are just general guidelines.

    The truth is, there is no magic standard for hydration—everyone's need vary depending on their age, weight, level of physical activity, general health and even the climate they live in. The more water you lose, the more water you'll need to replace with food and drink. If you are looking for concrete advice, though, the best place to look is within. Drink up when you're thirsty.

实验探究：

    圆是中国文化中的一个重要精神原型，它与中国人的宇宙意识、生命情调等有十分密切的关系，也是我们揭示中国艺术生命秘密的不可忽视的因素。人有悲欢离合，月有阴晴圆缺，圆有时是相对于缺而言的。我们通常所说的“圆满”一语，原是中国哲学的一个重要概念，其中也可看出中国人重视艺术生命的一份用心。司空图《诗品·雄浑》“超以象外，得其环中”云：“超以象外，至大不可限制；得其环中，理之圆足混成无缺，如太极然。”在这里，圆即充满、周备、具足，体现在诗性艺心就是浑全充融。森罗万象，一尘沤，一片叶，一缕云，及至浩浩苍天、绵绵大地，都可以大道涵括。

    中国哲学中有一个著名比喻：“月印万川”，最能体现充满圆融的特点。这个比喻有两层重要的含义：一是万川之月，只是一月。江流宛转绕芳甸，何处春江无月明，湛然寰宇，月光朗照，天下万千江湖，无处不映出它的圆影。然万千个圆共有一圆，万种之月，只有一月相照，一圆贯穿了万川之圆，散在江湖各处的异在之圆联成一个整体，只有一个生命。二是自此一月，可观全月。由于散在江湖的万千之月均由一月相照，故自任何一月均可窥见万千之月的内在生命，任何江湖的月都是一个自我完足的生命世界。“万川之月”所透析出的哲学内蕴就是：一即一切，一切即一，它强调了万物都是一个自在圆足的生命这一重要特性。

    　中国哲学的圆满具足说散发着浓厚的艺术情调，它实际上是以审美的眼光看待世界。儒道佛中的充满圆融的生命哲学刺激了中国艺术家的创造精神。由于受天人合一哲学观念的影响，中国艺术家总有一种自觉的超越意识，要尽广大，极精微，自有限而观无限，由当下而观永恒。然而宇宙洪阔，天道苍苍，艺术要受到时空的限制，它总不能摆脱具体的实在，总在关注一人一事一时一物，这便制约了艺术家的绵绵长思。万川之月自在圆融的生命哲学却给了破解这一难题的钥匙。艺术家既关心“一”，认为“山川即道”、“山水即天理”，万事万物均是道的化身，但更关心的是“一切”，因为“一切即一，一即一切”，一切都是自在圆足的生命整体。《文心雕龙》云：“乘一总万”；《二十四诗品》云：“万取一收”，其意大致相同。

    故中国艺术家更重视当下直接的观照，更关心微观，在艺术倾向上，两汉时铺排山川云物的现象到了唐宋时越来越少，人们所创造的艺术世界更加精微、细致。中唐以后，追求精微细致的审美风尚渐渐弥散开。如在中国园林中，人们普遍追求“壶纳天地”的妙处。一湾清泉，几条幽径，几处亭台，便俨然构成一自在圆足的世界。请看中国园林的命名：勺园，如一勺之大；蠡园，如一瓢之微；壶公楼，小得如茶壶一般；芥子园，微小得尤如一粒种子；一沤居，细微得如同大海中的一朵涟漪。但是，在中国人看，一沤就是茫茫大海，一假山就是连绵峰峦，一亭就是浩浩天庭。故人们常常将园林景区叫做“小沧浪”、“小蓬莱”、“小瀛洲”。“小”是园林特点，“沧浪”“瀛洲”等则是人们远的心意，壶公有天地，芥子纳须弥，这成了中国艺术家不言的秘诀。

    在中国山水画中，我们可以看到许多以“溪山无尽”为名的画，它反映了中国山水画家对山川无尽之妙的追求。王希孟的《千里江山图》和倪云林的《疏林秀石图》风格迥异，一是江山无限，一是片石只林，但所追求的却是一致的，人们在他们的画中无所憾，因为它们自身就是一个自我完足的宇宙。郭河阳“有人悟得丹青理，专向茅茨画山水”正谓此。若要能演成一个完整生命，“茅茨”也能成为灵区。

（节选自朱良志《论中国艺术论中的“圆”》，有修改）