“When you wish to instruct, be brief; that men’s minds may take in quickly what you say, learn its lesson, and retain it faithfully. Every word that is unnecessary only pours over the side of a brimming mind.”
Source: Ars Poetica, or The Epistle to the Pisones (c. 18 BC), Lines 335–337; Edward Charles Wickham translation
Original
Quidquid praecipies, esto brevis, ut cito dicta percipiant animi dociles teneantque fideles: omne supervacuum pleno de pectore manat.
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Horace 92
Roman lyric poet -65–-8 BCRelated quotes

Letter to Lawrence Crawford (10 March 1643)

Source: The Jewels of Aptor (1962), Chapter X (p. 133)
Context: A lesson which history should have taught us thousands of years ago was finally driven home. No man can wield absolute power over other men and still retain his own mind. For no matter how good his intentions are when he takes up the power, his alternate reason is that freedom, the freedom of other people and ultimately his own, terrifies him. Only a man afraid of freedom would want this power, who could conceive of wielding it. And that fear of freedom will turn him into a slave of this power.

Quoted on Yahoo News!, "First lady tells Kansas students to fight bias" (16 May 2014) http://news.yahoo.com/first-lady-tells-kansas-students-fight-bias-021747701.html
2010s
Aphorisms

Source: Haunted (2005), Chapter 4
Context: "It's not a matter of right and wrong," Mr. Whittier would say. Really, there is no wrong. Not in our minds. Our own reality. You can never set off to do the wrong thing. You can never say the wrong thing. In your own mind, you are always right. Every action you take--what you do or say or how you choose to appear--is automatically right the moment you act.
Middlebury College Address (2004)
Context: Be brave. Be open-minded. Be kind. Be forgiving. Be generous. Be optimistic. Be grateful for the many unexpected lessons you will learn. Find the joy inside the hardship. It’s there. I assure you. And, too, be open to inspiration from unlikely sources.

Sexy Plexi.
Song lyrics, Brushfire Fairytales (2001)