“The progressive development of moral and intellectual man has scarcely occupied their [scientists] attention; nor have they noted how the faculties of his mind are at every age influenced by those of the body, nor how his faculties mutually react.”

volume II, chapter XXI: "General Summary and Conclusion", page 393 http://darwin-online.org.uk/content/frameset?pageseq=410&itemID=F937.2&viewtype=image
The Descent of Man (1871)

1850s, Latter-Day Pamphlets (1850), Stump Orator (May 1, 1850)

The Minister's Wooing (1859) Ch. 1 Pre-Railroad Times.
Context: He was called a good fellow, — only a little lumpish, — and as he was brave and faithful, he rose in time to be a shipmaster. But when came the business of making money, the aptitude for accumulating, George found himself distanced by many a one with not half his general powers. What shall a man do with a sublime tier of moral faculties, when the most profitable business out of his port is the slave-trade? So it was in Newport in those days. George's first voyage was on a slaver, and he wished himself dead many a time before it was over, — and ever after would talk like a man beside himself, if the subject was named. He declared that the gold made in it was distilled from human blood, from mothers' tears, from the agonies and dying groans of gasping, suffocating men and women, and that it would sear and blister the soul of him that touched it; in short, he talked as whole-souled, unpractical fellows are apt to talk about what respectable people sometimes do. Nobody had ever instructed him that a slaveship, with a procession of expectant sharks in its wake, is a missionary institution, by which closely. packed heathens are brought over to enjoy the light of the Gospel. So, though George was acknowledged to be a good fellow, and honest as the noon-mark on the kitchen floor, he let slip so many chances of making money as seriously to compromise his reputation among thriving folks. He was wastefully generous — insisted on treating every poor dog that came in his way, in any foreign port, as a brother — absolutely refused to be party in cheating or deceiving the heathen on any shore, or in skin of any color — and also took pains, as far as in him lay, to spoil any bargains which any of his subordinates founded on the ignorance or weakness of his fellow-men. So he made voyage after voyage, and gained only his wages and the reputation among his employers of an incorruptibly honest fellow.

Pt. II, Ch. 4 : Derivation of a First Principle, § 3
Social Statics (1851)

Ten Sermons of Religion (1853), III : Of Justice and the Conscience https://en.wikisource.org/wiki/Ten_Sermons_of_Religion/Of_Justice_and_the_Conscience
Context: Man naturally loves justice, for its own sake, as the natural object of his conscience. As the mind loves truth and beauty, so conscience loves the right; it is true and beautiful to the moral faculties. Conscience rests in justice as an end, as the mind in truth. As truth is the side of God turned towards the intellect, so is justice the side of Him which conscience looks upon. Love of justice is the moral part of piety.

Draft for a Statement of Human Obligation (1943)
Context: If anyone possesses this faculty, then his attention is in reality directed beyond the world, whether he is aware of it or not.
The link which attaches the human being to the reality outside the world is, like the reality itself, beyond the reach of human faculties. The respect that it makes us feel as soon as it is recognized cannot be shown to us by evidence or testimony.

Introductory
A Treatise on Man and the Development of His Faculties (1842)

The First Part, Chapter 11, p. 47
Leviathan (1651)

The Nature, Importance and Liberties of Belief (1873)
Context: Now, evidence to a man is that which convinces his mind. It varies with different men. An argument to a man who cannot reason is no evidence. Facts are no evidence to a man who cannot perceive them. A sentimental appeal is evidence to a man whose very nature moves by emotion, though it may not be to his neighbor.
So then, when men come to the investigation of truth, they are responsible, first, for research, for honesty therein, for being diligent, and for attempting to cleanse their minds from all bias of selfishness and pride. They are responsible for sincerity and faithfulness in the investigation of truth. And when they go beyond that to the use of their faculties, the combination of those faculties will determine very largely, not, perhaps, the generic nature of truth, but specific developments of it. And as long as the world stands there will be men who will hold that God is a God of infinite love and sympathy and. goodness with a residunm of justice; and there will be men who will believe that God is a God of justice with a residunm of love and sympathy and goodness; and each will follow the law of his own mind. As a magnet, drawn through a vessel containing sand and particles of iron, attracts the particles of iron but does not attract the sand; so the faculties of a man's mind appropriate certain facts and reject others. What is evidence to a man will depend upon those of his faculties whk at work upon the things which are presented as evidence.