“Thoughts that cannot survive the open air and that evaporate as soon as we take them out of the room. To put them to the test of isolation. Take them out of the book where you found them, they do not endure.”

"The Case for the Ephemeral"
All Things Considered (1908)
Context: I cannot understand the people who take literature seriously; but I can love them, and I do. Out of my love I warn them to keep clear of this book. It is a collection of crude and shapeless papers upon current or rather flying subjects; and they must be published pretty much as they stand. They were written, as a rule, at the last moment; they were handed in the moment before it was too late, and I do not think that our commonwealth would have been shaken to its foundations if they had been handed in the moment after. They must go out now, with all their imperfections on their head, or rather on mine; for their vices are too vital to be improved with a blue pencil, or with anything I can think of, except dynamite.
Their chief vice is that so many of them are very serious; because I had no time to make them flippant. It is so easy to be solemn; it is so hard to be frivolous.

Reportedly said in a meeting with lawmakers on immigration, as quoted in "'Sh*thole countries' respond to Trump's rhetoric" https://www.cbsnews.com/news/donald-trump-shthole-countries-response-from-haiti-africa-el-salvador/?ftag=CNM-00-10aab8a&linkId=46885064, CBS News. Trump denied making this comment.
"Never said anything derogatory about Haitians other than Haiti is, obviously, a very poor and troubled country. Never said "take them out." Made up by Dems. I have a wonderful relationship with Haitians. Probably should record future meetings - unfortunately, no trust!" Tweet by @realDonaldTrump https://twitter.com/realDonaldTrump/status/951813216291708928 (12 January 2018)
Disputed

King's words after a bomb was thrown into his house in Alabama, on 30 January 1956, in Stride Toward Freedom (1958)
1950s
Context: If you have weapons, take them home; if you do not have them, please do not seek to get them. We cannot solve this problem through retaliatory violence. We must meet violence with nonviolence. Remember the words of Jesus: "He who lives by the sword will perish by the sword." We must love our white brothers, no matter what they do to us. We must make them know that we love them. Jesus still cries out in words that echo across the centuries: "Love your enemies; bless them that curse you; pray for them that despitefully use you." This is what we must live by. We must meet hate with love. Remember, if I am stopped, this movement will not stop, because God is with the movement. Go home with this glowing faith and this radiant assurance.

#92
Vectors: Aphorisms and Ten Second Essays (2001)

CNN interview, October 12, 2009. http://nymag.com/daily/intel/2009/10/white_house_reveals_tactics_in.html