“War unleashes – at the same time as the reactionary forces of the capitalist world – the generating forces of social revolution which ferment in its depths.”

Part V : The Economics of a Socialist Community, § V : Destructionism, Ch. 33 : The Motive Powers of Destructionism, p. 440 http://www.econlib.org/library/Mises/msS12.html#V.34.35,Ch.33
Socialism (1922)

Remarks by German Chancellor Angela Merkel before a joint session of Congress on November 04, 2009. http://www.spiegel.de/international/europe/0,1518,659196,00.html
Dokumentation: Angela Merkels Rede im US-Kongress im Wortlaut http://www.welt.de/politik/ausland/article5079678/Angela-Merkels-Rede-im-US-Kongress-im-Wortlaut.html
Context: Freedom is the very essence of our economy and society. Without freedom the human mind is prevented from unleashing its creative force. But what is also clear is that this freedom does not stand alone. It is freedom in responsibility and freedom to exercise responsibility.

"The Scientific Revolution and the Machine"
The Common Sense of Science (1951)

Cuba as Vanguard (1961)

The Transhumanism Handbook, 2019

Method of Guerrilla Warfare (1963)

Letter published in The Tribune (25 December 1929), with some reference to lines from Idylls of the King by Alfred Tennyson
Context: Revolution did not necessarily involve sanguinary strife. It was not a cult of bomb and pistol. They may sometimes be mere means for its achievement. No doubt they play a prominent part in some movements, but they do not — for that very reason — become one and the same thing. A rebellion is not a revolution. It may ultimately lead to that end.
The sense in which the word Revolution is used in that phrase, is the spirit, the longing for a change for the better. The people generally get accustomed to the established order of things and begin to tremble at the very idea of a change. It is this lethargical spirit that needs be replaced by the revolutionary spirit. Otherwise degeneration gains the upper hand and the whole humanity is led stray by the reactionary forces. Such a state of affairs leads to stagnation and paralysis in human progress. The spirit of Revolution should always permeate the soul of humanity, so that the reactionary forces may not accumulate to check its eternal onward march. Old order should change, always and ever, yielding place to new, so that one “good” order may not corrupt the world. It is in this sense that we raise the shout “Long Live Revolution.”

Progress, Coexistence and Intellectual Freedom (1968), The Basis for Hope, Peaceful Competition
Context: Without socialism, bourgeois practices and the egotistical principle of private ownership gave rise to the "people of the abyss" described by Jack London and earlier by Engels.
Only the competition with socialism and the pressure of the working class made possible the social progress of the twentieth century and, all the more, will insure the now inevitable process of rapprochement of the two systems. It took socialism to raise the meaning of labor to the heights of a moral feat. Before the advent of socialism, national egotism gave rise to colonial oppression, nationalism, and racism. By now it has become clear that victory is on the side of the humanistic, international approach.
The capitalist world could not help giving birth to the socialist, but now the socialist world should not seek to destroy by force the ground from which it grew. Under the present conditions this would be tantamount to the suicide of mankind. Socialism should ennoble that ground by its example and other indirect forms of pressure and then merge with it.

Source: How Europe Underdeveloped Africa (1972), p. 310.