“Leaving virtue without proper cultivation; not thoroughly discussing what is learned; not being able to move towards righteousness of which a knowledge is gained; and not being able to change what is not good: — these are the things which occasion me solicitude.”

To keep silently in mind what one has seen and heard, to study hard and never feel contented, to teach others tirelessly; have I done (all of) these things?
Source: The Analects, Other chapters

Source: Tao of Jeet Kune Do

"Bible Stories for Adults, No. 20: The Tower" p. 76 (originally published in Author’s Choice Monthly #8: Swatting at the Cosmos)
Short fiction, Bible Stories for Adults (1996)

Source: Kingdom Hearts, Vol. 1

Source: Reason: The Only Oracle Of Man (1784), Ch. IV Section II - Containing a Disquisition of the Law of Nature, as it respects the Moral System, interspersed with Observations on Subsequent Religions.

Source: The Cave (2000), p. 20 (Vintage 2003)

The Book of My Life (1930)
Context: My father, in my earliest childhood, taught me the rudiments of arithmetic, and about that time made me acquainted with the arcana; whence he had come by this learning I know not. This was about my ninth year. Shortly after, he instructed me in the elements of the astronomy of Arabia, meanwhile trying to instill in me some system of theory for memorizing, for I had been poorly endowed with the ability to remember. After I was twelve years old he taught me the first six books of Euclid, but in such a manner that he expended no effort on such parts as I was able to understand by myself.
This is the knowledge I was able to acquire and learn without any elementary schooling...<!--Ch. 34

The Tragic Sense of Life (1913), VII : Love, Suffering, Pity

Source: Anthem singer sings and believes in O Canada https://web.archive.org/web/20150725124144/http://www.bccatholic.ca/the-news/1775-anthem-singer-sings-and-believes-in-o-canada (23 June 2012)