“All these battles spring from themselves and necessitate each other to infinity! One single battle is not enough, it is not complete, there is no satisfaction. Nothing is finished, nothing is ever finished. Ah, it is only men who die! No one understands the greatness of things, and I know well that I do not understand all the horror in which I am.”

Source: Galileo's Dream (2009), Ch. 15, p. 354; note: though this statement is incorporated into the story as one Galileo spoke, it is actually a quotation of one he historically made in his Dialogue Concerning The Two Chief World Systems http://www4.ncsu.edu/~kimler/hi322/Dialogue-extracts.html as translated by Stillman Drake.

Conclusion : The Moral of this Examination
A Perplexed Philosopher (1892)
Context: I care nothing for creeds. I am not concerned with any one's religious belief. But I would have men think for themselves. If we do not, we can only abandon one superstition to take up another, and it may be a worse one. It is as bad for a man to think that he can know nothing as to think he knows all. There are things which it is given to all possessing reason to know, if they will but use that reason. And some things it may be there are, that — as was said by one whom the learning of the time sneered at, and the high priests persecuted, and polite society, speaking through the voice of those who knew not what they did, crucified — are hidden from the wise and prudent and revealed unto babes.

Después de tanto huir de las cosas hechas, me he encontrado yo mismo una cosa hecha. Y sigo huyendo de las cosas hechas.
Voces (1943)

Source: Life, the Truth, and Being Free (2010), p. 155

Attributed to "Hericletus c. 500 B.C." [sic] in The Tactical Rifle https://books.google.com/books?id=xO7XAAAAMAAJ&dq=%22They+make+the+battle.+Ah+but+the+One%2C+One+of+them+is+a+Warrior%22&focus=searchwithinvolume&q=%22He+will+bring+the+others+back%22 (1999) by Gabriel Suarez; no earlier source has been found.
Misattributed

"Thirty-three Happy Moments"

Pink Floyd: Live at Pompeii
Music

Entry in her journal (10 October 1922) which she tore out to send to John Middleton Murry, before changing her mind. This later became the last published entry in The Journal of Katherine Mansfield (1927) ed. J. Middleton Murry
Context: By health I mean the power to live a full, adult, living, breathing life in close contact with what I love — the earth and the wonders thereof — the sea — the sun. All that we mean when we speak of the external world. A want to enter into it, to be part of it, to live in it, to learn from it, to lose all that is superficial and acquired in me and to become a conscious direct human being. I want, by understanding myself, to understand others. I want to be all that I am capable of becoming so that I may be (and here I have stopped and waited and waited and it’s no good — there’s only one phrase that will do) a child of the sun. About helping others, about carrying a light and so on, it seems false to say a single word. Let it be at that. A child of the sun.

Source: The Vampire Armand