“Sometimes letting things go is an act of far greater power than defending or hanging on.”

Education (1902)
Context: I am not of those who believe in lackadaisical methods. On the contrary, I advocate a vigorous, thorough, exact mental training which shall fit the mind to expand upon and grasp large things and yet properly to perceive in their just relation the significance of small ones to discriminate accurately as to quantity and quality and thus to develop individual judgment, capacity and independence.
But at the same time I am of those who believe that gentleness is a greater, surer power than force, and that sympathy is a safer power by far than is intellect. Therefore would I train the individual sympathies as carefully in all their delicate warmth and tenuity as I would develop the mind in alertness, poise and security.
Nor am I of those who despise dreamers. For the world would be at the level of zero were it not for its dreamers gone and of today. He who dreamed of democracy, far back in a world of absolutism, was indeed heroic, and we of today awaken to the wonder of his dream.

Le forze della penna sono troppo maggiori che coloro non estimano che quelle con conoscimento provato non hanno.
Eighth Day, Seventh Story
The Decameron (c. 1350)

The Ballad of the King's Jest, Stanza 4
Other works

Source: The Da Vinci Code

No. 50
On the Interpretation of Nature (1753)

Source: Tuesdays with Morrie (1997)

Source: Meditations (c. 121–180 AD), Book VIII, 54