“In proportion as I advance in life, I grow more simple, and I become more and more patriotic for humanity.”

1970s-, The Captains, the Kings, and Taylor Caldwell (1978)
Context: You’ve got to look at life clearly. No rose-colored glasses. The human race is not very admirable. It was a big mistake of God’s... The more I see of people, the more bitter I become. I think I appeal to readers because there’s nothing false or hypocritical in what I write. And they recognize themselves, and recognize their fears. And they know what bastards they are.

Optimism
Poetry quotes, Poems of Pleasure (1900)
Context: I find a rapture linked with each despair,
Well worth the price of anguish. I detect
More good than evil in humanity.
Love lights more fires than hate extinguishes,
And men grow better as the world grows old.

Hagakure (c. 1716)
Context: A certain swordsman in his declining years said the following: In one's life. there are levels in the pursuit of study. In the lowest level, a person studies but nothing comes of it, and he feels that both he and others are unskillful. At this point he is worthless. In the middle level he is still useless but is aware of his own insufficiencies and can also see the insufficiencies of others. In a higher level he has pride concerning his own ability, rejoices in praise from others, and laments the lack of ability in his fellows. This man has worth. In the highest level a man has the look of knowing nothing. These are the levels in general;. But there is one transcending level, and this is the most excellent of all. This person is aware of the endlessness of entering deeply into a certain Way and never thinks of himself as having finished. He truly knows his own insufficiencies and never in his whole life thinks that he has succeeded. He has no thoughts of pride but with self-abasement knows the Way to the end. It is said that Master Yagyu once remarked, "I do not know the way to defeat others, but the way to defeat myself." Throughout your life advance daily, becoming more skillful than yesterday, more skillful than today. This is never-ending.

from the meditations of Jin Zenimura
Neverness (1988)

Book II, ch. 4 (trans. Constance Garnett)
The Elder Zossima, speaking to Mrs. Khoklakov
The Brothers Karamazov (1879–1880)
Context: "It's just the same story as a doctor once told me," observed the elder. "He was a man getting on in years, and undoubtedly clever. He spoke as frankly as you, though in jest, in bitter jest. 'I love humanity,' he said, 'but I wonder at myself. The more I love humanity in general, the less I love man in particular. In my dreams,' he said, 'I have often come to making enthusiastic schemes for the service of humanity, and perhaps I might actually have faced crucifixion if it had been suddenly necessary; and yet I am incapable of living in the same room with any one for two days together, as I know by experience. As soon as any one is near me, his personality disturbs my self-complacency and restricts my freedom. In twenty-four hours I begin to hate the best of men: one because he's too long over his dinner; another because he has a cold and keeps on blowing his nose. I become hostile to people the moment they come close to me. But it has always happened that the more I detest men individually the more ardent becomes my love for humanity.'"

The Philosophy of Atheism (1916)

2010-, Ai Weiwei: 'Every day I think, this will be the day I get taken in again...', 2011

Letter to George Richard Minot (May 27, 1789); reported in Works of Fisher Ames (1854), ed. Seth Ames, vol. 1, p. 45.

"Quotes", The Educated Imagination (1963), Talk 2: The Singing School