We live in a world of shadows, and what we call reality is only the shadow of a shadow.
I have called this principle, by which each slight variation, if useful, is preserved, by the term Natural Selection.  
Every challenge is an opportunity to grow stronger and wiser.
最有力的艺术是让我们感到不安的艺术,它迫使我们面对我们宁愿忽视的东西。
There are tracts in my life that are bare and silent. They are the open spaces where my busy days had their light and air.
The ultimate tragedy is not the oppression and cruelty by the bad people but the silence over that by the good people.