What doesn't kill you make you stronger.

This is what is hardest: to close the open hand because one loves.

Ah, there are so many things betwixt heaven and earth of which only the poets have dreamed!

Only idiots fail to contradict themselves three times a day.

The masters have been done away with; the morality of the common man has triumphed.

Science ... has no consideration for ultimate purposes, any more than Nature has, but just as the latter occasionally achieves things of the greatest suitableness without intending to do so, so also true science, as the imitator of nature in ideas, will occasionally and in many ways further the usefulness and welfare of man,-but also without intending to do so.

This life as you now live it and have lived it, you will have to live once more and innumerable times more; and there will be nothing new in it, but every pain and every joy and every thought and sigh and everything unutterably small or great in your life will have to return to you, all in the same succession and sequence - even this spider and this moonlight between the trees, and even this moment and I myself. The eternal hourglass of existence is turned upside down again and again, and you with it, speck of dust!