“What our story, however, has demonstrated is the astonishingly checkered, not to say hazardous, career of a reading device which we in the West now take so much for granted. Historians have acclaimed the "triumph of the alphabet," but the triumph was often compromised, sometimes bitterly contested, and to this day is only half won.”

Speech before the Naval War College, Newport, Rhode Island (June 1897), reported in "Washington’s Forgotten Maxim", American Ideals (1926), vol. 13 of The Works of Theodore Roosevelt, national ed., chapter 12, p. 198
1890s

Remarks by the President at LBJ Presidential Library Civil Rights Summit at Lyndon B. Johnson Presidential Library in Austin, Texas on April 10, 2014. http://www.whitehouse.gov/the-press-office/2014/04/10/remarks-president-lbj-presidential-library-civil-rights-summit
2014

Source: Memoirs of the Second World War

1940s, Victory broadcast (1945)
Context: We have known the bitterness of defeat and the exultation of triumph, and from both we have learned there can be no turning back. We must go forward to preserve in peace what we won in war.
A new era is upon us. Even the lesson of victory itself brings with it profound concern, both for our future security and the survival of civilization. The destructiveness of the war potential, through progressive advances in scientific discovery, has in fact now reached a point which revises the traditional concepts of war.

"Niall Ferguson: 'Westerners don't understand how vulnerable freedom is'" https://www.theguardian.com/books/2011/feb/20/niall-ferguson-interview-civilization, The Guardian, February 20, 2011.

Source: Black Reconstruction in America (1935), p. 713

Mutual Aid: A Factor of Evolution (1902)
Context: As to the sudden industrial progress which has been achieved during our own century, and which is usually ascribed to the triumph of individualism and competition, it certainly has a much deeper origin than that. Once the great discoveries of the fifteenth century were made, especially that of the pressure of the atmosphere, supported by a series of advances in natural philosophy — and they were made under the medieval city organization, — once these discoveries were made, the invention of the steam-motor, and all the revolution which the conquest of a new power implied, had necessarily to follow... To attribute, therefore, the industrial progress of our century to the war of each against all which it has proclaimed, is to reason like the man who, knowing not the causes of rain, attributes it to the victim he has immolated before his clay idol. For industrial progress, as for each other conquest over nature, mutual aid and close intercourse certainly are, as they have been, much more advantageous than mutual struggle.

Source: Aphorisms and Reflections (1901), pp. 234-235

Vorkosigan Saga, Mirror Dance (1994)