曾听说过这样一个故事:从前,有位渔夫出海打鱼,从海里捞到一颗大珍珠。这颗珍珠晶莹圆润,渔夫爱不释手。但美中不足的是,珍珠上面有一个小黑点。渔夫心想,如果能把小黑点去掉,珍珠就完美无瑕了,一定会成为无价之宝。于是,他耐心地剥去黑点。可是去掉一层,黑点依然存在;再去掉一层,黑点还是存在;再去掉一层……最后终于去掉了。不过,令人惋惜的 Have heard of such a story: In the past, a fisherman to go fishing, fishing from the sea to a large pearl. This pearl crystal mellow, fisherman put it down. But the fly in the ointment is that there is a little black pearl above. Fisherman thought, if you can remove the black spots, pearl perfect, will certainly become priceless treasure. So, he peeled off the black spots patiently. But get rid of a layer of black spots still exist; then remove the layer, black spots still exist; then remove the layer ... ... Finally finally removed. However, it is regrettable