“We are all civilized people, wich means that we are all savages at heart but observing a few amenities of civilized behaviour.”

Truman Library address (2006)
Context: My friends, our challenge today is not to save Western civilization — or Eastern, for that matter. All civilization is at stake, and we can save it only if all peoples join together in the task.
You Americans did so much, in the last century, to build an effective multilateral system, with the United Nations at its heart. Do you need it less today, and does it need you less, than 60 years ago?
Surely not. More than ever today, Americans, like the rest of humanity, need a functioning global system through which the world’s peoples can face global challenges together. And in order to function more effectively, the system still cries out for far-sighted American leadership, in the Truman tradition.
I hope and pray that the American leaders of today, and tomorrow, will provide it.

Source: The Story of Civilization (1935–1975), VI - The Reformation (1957), Chapter 6, p. 229

Source: Walden

Greeting to the American Committee for Protection of Foreign-born (9 January 1940); later inscribed on the Franklin Delano Roosevelt Memorial.
1940s

Source: "The New Russia" 1928, p. 24

Sec. 145
Some Thoughts Concerning Education (1693)
Context: The Indians, whom we call barbarous, observe much more decency and civility in their discourses and conversation, giving one another a fair silent hearing till they have quite done; and then answering them calmly, and without noise or passion. And if it be not so in this civiliz'd part of the world, we must impute it to a neglect in education, which has not yet reform'd this antient piece of barbarity amongst us.

Source: Who? (1958), p. 53

Speech at the Dedication of Great Smoky Mountains National Park, September 2, 1940
1940s

Scottish Folklore and Opera (1992).