“The moral truth here is obvious: anyone who feels that the interests of a blastocyst just might supersede the interests of a child with a spinal cord injury has had his moral sense blinded by religious metaphysics.”

Speech at Springfield, Illinois (26 June 1857)
1850s, Speech on the Dred Scott Decision (1857)

Part III : Selection on Education from Kant's other Writings, Ch. I Pedagogical Fragments, # 58
The Educational Theory of Immanuel Kant (1904)

Source: The World As I See It

As quoted in "Literary Censorship in England" in Current Opinion, Vol. 55, No. 5 (November 1913), p. 378; this has sometimes appeared on the internet in paraphrased form as "Censorship ends in logical completeness when nobody is allowed to read any books except the books that nobody reads"
1910s
Context: Any public committee man who tries to pack the moral cards in the interest of his own notions is guilty of corruption and impertinence. The business of a public library is not to supply the public with the books the committee thinks good for the public, but to supply the public with the books the public wants. … Censorship ends in logical completeness when nobody is allowed to read any books except the books that nobody can read. But as the ratepayer is mostly a coward and a fool in these difficult matters, and the committee is quite sure that it can succeed where the Roman Catholic Church has made its index expurgatorius the laughing-stock of the world, censorship will rage until it reduces itself to absurdity; and even then the best books will be in danger still.

Interview with The Guardian http://www.guardian.co.uk/music/2011/nov/27/jarvis-cocker-pulp-readers-questions (2011)

Looking for an Honest Man (2009)
Context: With his attractive picture of human flourishing, Aristotle offers lasting refuge against the seas of moral relativism. Taking us on a tour of the museum of the virtues — from courage and moderation, through liberality, magnificence, greatness of soul, ambition, and gentleness, to the social virtues of friendliness, truthfulness, and wit — and displaying each of their portraits as a mean between two corresponding vices, ­Aristotle gives us direct and immediate experience in seeing the humanly beautiful. Anyone who cannot see that courage is more beautiful than cowardice or rashness, or that liberality is more beautiful than miserliness or prodigality, suffers, one might say, from the moral equivalent of color-blindness.

Letter to William Sotheby (10 September 1802)
Letters

as quoted in From Rebel to Rabbi: Reclaiming Jesus and the Making of Modern Jewish Culture, Matthew B. Hoffman; Stanford University Press, 2007, p. 219
after 1930