“Precisely because Marx was convinced that the cause of the proletariat was of decisive importance for the whole future of mankind, he wanted to create for that cause not a flimsy platform of rhetorical invective or wishful thinking, but the rock-like foundation of scientific truth.”

Rodong Sinmun (25 December 1995) "Respecting the forerunners of the revolution is a noble moral obligation of revolutionaries" http://www.korea-dpr.com/library/206.pdf

1770s, Common Sense (1776)
Context: The cause of America is in a great measure the cause of all mankind. Many circumstances hath, and will arise, which are not local, but universal, and through which the principles of all Lovers of Mankind are affected, and in the Event of which, their Affections are interested. The laying a Country desolate with Fire and Sword, declaring War against the natural rights of all Mankind, and extirpating the Defenders thereof from the Face of the Earth, is the Concern of every Man to whom Nature hath given the Power of feeling; of which Class, regardless of Party Censure, is the AUTHOR.

1900s, Inaugural Address (1905)
Context: The conditions which have told for our marvelous material well-being, which have developed to a very high degree our energy, self-reliance, and individual initiative, have also brought the care and anxiety inseparable from the accumulation of great wealth in industrial centers. Upon the success of our experiment much depends, not only as regards our own welfare, but as regards the welfare of mankind. If we fail, the cause of free self-government throughout the world will rock to its foundations, and therefore our responsibility is heavy, to ourselves, to the world as it is to-day, and to the generations yet unborn.

1960, The New Frontier

“The Phaedrus and the Nature of Rhetoric,” p. 24.
The Ethics of Rhetoric (1953)

1950s, Rediscovering Lost Values (1954)
Context: There is something wrong with our world, something fundamentally and basically wrong. I don't think we have to look too far to see that. I'm sure that most of you would agree with me in making that assertion. And when we stop to analyze the cause of our world's ills, many things come to mind. We begin to wonder if it is due to the fact that we don't know enough. But it can't be that. Because in terms of accumulated knowledge we know more today than men have known in any period of human history. We have the facts at our disposal. We know more about mathematics, about science, about social science, and philosophy than we've ever known in any period of the world's history. So it can't be because we don't know enough. And then we wonder if it is due to the fact that our scientific genius lags behind. That is, if we have not made enough progress scientifically. Well then, it can't be that. For our scientific progress over the past years has been amazing. Man through his scientific genius has been able to dwarf distance and place time in chains, so that today it's possible to eat breakfast in New York City and supper in London, England. Back in about 1753 it took a letter three days to go from New York City to Washington, and today you can go from here to China in less time than that. It can't be because man is stagnant in his scientific progress. Man's scientific genius has been amazing. I think we have to look much deeper than that if we are to find the real cause of man's problems and the real cause of the world's ills today. If we are to really find it I think we will have to look in the hearts and souls of men.

Alan Dershowitz, The Best Defense (New York: Vintage), 1983-5-12, p. xiv.

Source: The Son of Neptune

The Art of Magic (1891)
Context: No one regards the magician today as other than an ordinary man gifted with no extraordinary powers. The spectators come, not to be impressed with awe, but fully aware that his causes and effects are natural. They come rather as a guessing committee, to spy out the methods with which he mystifies. Hundreds of eyes are upon him. Men with more knowledge of the sciences than he come to trip and expose him, and to baffle their scrutiny is the study of his life. Long years of training and exercise alone will not make a magician. … There must be some natural aptitude for the art; it must be born in a man, and can never be acquired by rule. He must be alert both in body and in mind; cool and calculating to the movement of a muscle under all circumstances; a close student of men and human nature. To these qualifications he must add the rather incongruous quality of a mind turning on contradictions. With a scientific cause he must produce a seemingly opposite effect to that warranted by order and system.
I know of no life requiring such a series of opposite qualities as the magician's. And after the exercise of all these qualities I have named, resulting in the production of the most startling and novel results, the magician has not the satisfaction, like other men, of the enjoyment of his own product. He must be prepared to see it copied by others, or after a short time discovered by the public.