“Kandinsky in Munich uttered the well known words: 'Everything is permitted!' In 1961; we still live by this heritage, which in truth is inexhaustible.”

Sand and Foam (1926)

Source: Nietzsche (1961), p. xxxix

Letter to Adrianna Enriques (October 1921), p. 83
Attributed in posthumous publications, Albert Einstein: The Human Side (1979)

Source: The Key to Theosophy (1889)

Source: 1984

Source: The Bait Of Satan: Living Free from the Deadly Trap of Offense

The Sheltering Sky (1949)
Context: Because we don't know when we will die, we get to think of life as an inexhaustible well. Yet everything happens only a certain number of times, and a very small number really. How many more times will you remember a certain afternoon of your childhood, some afternoon that is so deeply a part of your being that you can't even conceive of your life without it? Perhaps four or five times more, perhaps not even that. How many more times will you watch the full moon rise? Perhaps twenty. And yet it all seems limitless.

"Proclamation 3560 — Thanksgiving Day, 1963" (5 November 1963) http://www.presidency.ucsb.edu/ws/?pid=9511<!-- Online by Gerhard Peters and John T. Woolley, The American Presidency Project -->
1963
Context: Today we give our thanks, most of all, for the ideals of honor and faith we inherit from our forefathers —  for the decency of purpose, steadfastness of resolve and strength of will, for the courage and the humility, which they possessed and which we must seek every day to emulate. As we express our gratitude, we must never forget that the highest appreciation is not to utter words but to live by them.
Let us therefore proclaim our gratitude to Providence for manifold blessings — let us be humbly thankful for inherited ideals — and let us resolve to share those blessings and those ideals with our fellow human beings throughout the world.

Preface to the first edition
Source: The Selfish Gene (1976, 1989)