叶芝诗句这世上的眼泪太多你不会懂得出自

这句话“这世上的眼泪太多你不会懂得”出自爱尔兰诗人威廉·巴特勒·叶芝（W.B. Yeats）的诗作《When You Are Old》。这首诗是叶芝为纪念他的爱人茅德·冈而作，表达了对爱情、时光流逝和生命无常的感慨。全诗如下：

When you are old and grey and full of sleep,

And nodding by the fire, take down this book,

And slowly read, and dream of the soft look

Your eyes had once, and of their shadows deep;

How many loved your moments of glad grace,

And loved your beauty with love false or true,

But one man loved the pilgrim soul in you,

And loved the sorrows of your changing face;

And bending down beside the glowing bars,

Murmur, a little sadly, how Love fled

And paced upon the mountains overhead

And hid his face amid a crowd of stars.

这首诗情感深沉，语言优美，是叶芝诗歌中的佳作之一。