“We are living in a time of dissent, upheaval, revolutions and struggle, frequently aimed at mutual destruction.”

Source: Red Glove

Source: The Psychology of Personal Constructs, 1955, p. 775

“Lessons of the Commune”, in Zagranichnaya Gazeta, No. 2 (23 March 1908) http://www.marx.org/archive/lenin/works/1908/mar/23.htm, as translated by Bernard Isaacs, Collected Works, Vol. 13, p. 478.
1900s
Variant: The proletariat should not ignore peaceful methods of struggle — they serve its ordinary, day-to-day interests, they are necessary in periods of preparation for revolution — but it must never forget that in certain conditions the class struggle assumes the form of armed conflict and civil war; there are times when the interests of the proletariat call for ruthless extermination of its enemies in open armed clashes. This was first demonstrated by the French proletariat in the Commune and brilliantly confirmed by the Russian proletariat in the December uprising.

Address given in Copenhagen "Physics in Denmark: The First Four Hundred Years" (6 March 1996) http://nobelprize.org/nobel_prizes/physics/articles/pais/index.html?print=1
Context: Today we live in the midst of upheaval and crisis. We do not know where we are going, nor even where we ought to be going. Awareness is spreading that our future cannot be a straight extension of the past or the present … The century now approaching its end has been one of indiscriminate violence, it has been perhaps the most murderous one in Western history of which we have record. Yet I would think that what will strike people most when, hundreds of years from now, they will look back on our days is that this was the age when the exploration of space began, the microchip was invented, revolutions in transport and communication virtually annihilated time and distance, transforming the world into a "global village," and relativity theory, quantum mechanics, and the structure of the atom were discovered, in brief that this has been the century of science and technology.

"Mutual Aid as a Factor in Evolution" as quoted in The Cry for Justice : An Anthology of the Literature of Social Protest (1915) by Upton Sinclair
Context: A soon as we study animals — not in laboratories and museums only, but in the forest and prairie, in the steppe and in the mountains — we at once perceive that though there is an immense amount of warfare and extermination going on amidst various species, and especially amidst various classes of animals, there is, at the same time, as much, or perhaps even more, of mutual support, mutual aid, and mutual defence amidst animals belonging to the same species or, at least, to the same society. Sociability is as much a law of nature as mutual struggle. Of course it would be extremely difficult to estimate, however roughly, the relative numerical importance of both these series of facts. But if we resort to an indirect test, and ask Nature: "Who are the fittest: those who are continually at war with each other, or those who support one another?" we at once see that those animals which acquire habits of mutual aid are undoubtedly the fittest. They have more chances to survive, and they attain, in their respective classes, the highest development and bodily organization. If the numberless facts which can be brought forward to support this view are taken into account, we may safely say that mutual aid is as much a law of animal life as mutual struggle; but that as a factor of evolution, it most probably has a far greater importance, inasmuch as it favors the development of such habits and characters as insure the maintenance and further development of the species, together with the greatest amount of welfare and enjoyment of life for the individual, with the least waste of energy.

Source: 1960s, Robots, Men and Minds (1967), p. 57

Speech delivered on September 6, 1990, before the Annual Judicial Conference of the Second Circuit, quoted in Supreme Justice Speeches and Writings Thurgood Marshall. Edited by J. Clay Smith, Jr. (2002).

The Red Army Faction: A Documentary History, Volume One: Projectiles for the People.