光的世界里，是一个鸟语花香的世界。
In that world of light there were birds singing, and beautiful flowers bloomed.
我们进化于一个飞禽走兽，鸟语花香、山石林立、万物繁盛的自然世界，因而自然界是我们得到愉悦感与满足感的源泉。
一个双目失明的盲人，他没有白天和黑夜的一丝概念，看不到鸟语花香，看不到高山流水，他看不到柳绿桃红的世界万物，他甚至不知道灯光是什么样子的，他挑一盏灯笼岂不令人迷惘和可笑？
A blind man was supposed to have no concept of day and night and cannot see everything like birds, flowers, mountains, waters, etc, around him. He could even not know how the "light" looked like.
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