“One just principle from the depths of a cave is more powerful than an army.”

"Of Love" as translated in The Infinite in Giordano Bruno : With a Translation of His Dialogue, Concerning the Cause, Principle, and One (1978) by Sidney Thomas Greenburg, p. 89
Variant translation:
Cause, Principle and One, the Sempiterne,
On whom all being, motion, life, depend.
From whom, in length, breadth, depth, their paths extend
As far as heaven, earth, hell their faces turn :
With sense, with mind, with reason, I discern
That not, rule, reckoning, may not comprehend
That power and bulk and multitude which tend
Beyond all lower, middle, and superne. <p> Blind error, ruthless time, ungentle doom,
Deaf envy, villain madness, zeal unwise,
Hard heart, unholy craft, bold deeds begun,
Shall never fill for one the air with gloom,
Or ever thrust a veil before these eyes,
Or ever hide from me my glorious sun.
As quoted in "Giordano Bruno" by Thomas Davidson, The Index Vol. VI. No. 36 (4 March 1886), p. 429
Cause, Principle, and Unity (1584)
Context: Cause, Principle, and One eternal
From whom being, life, and movement are suspended,
And which extends itself in length, breadth, and depth,
To whatever is in Heaven, on Earth, and Hell;
With sense, with reason, with mind, I discern,
That there is no act, measure, nor calculation, which can comprehend
That force, that vastness and that number,
Which exceeds whatever is inferior, middle, and highest;
Blind error, avaricious time, adverse fortune,
Deaf envy, vile madness, jealous iniquity,
Crude heart, perverse spirit, insane audacity,
Will not be sufficient to obscure the air for me,
Will not place the veil before my eyes,
Will never bring it about that I shall not
Contemplate my beautiful Sun.

As quoted in Memoirs of General W.T. Sherman, 2nd ed., D. Appleton & Co., 1913 (1889). Reprinted by the Library of America, 1990<!--, ,--> p. 729.
1880s
Context: My aim then was to whip the rebels, to humble their pride, to follow them to their inmost recesses, and make them fear and dread us. 'Fear of the Lord is the beginning of wisdom.' I did not want them to cast in our teeth what General Hood had once done at Atlanta, that we had to call on their slaves to help us to subdue them. But, as regards kindness to the race..., I assert that no army ever did more for that race than the one I commanded at Savannah.

1790s, Agrarian Justice (1797)
Source: Common Sense, The Rights of Man and Other Essential Writings
Context: An army of principles will penetrate where an army of soldiers cannot; it will succeed where diplomatic management would fall: it is neither the Rhine, the Channel, nor the ocean that can arrest its progress: it will march on the horizon of the world, and it will conquer.

(zh-CN) 军队须和民众打成一片，使军队在民众眼睛中看成是自己的军队，这个军队便无敌于天下，个把日本帝国主义是不够打的。
1930s, On Protracted Warfare (1938)

Letter to John Taylor (28 May 1816) ME 15:23 http://www.britannica.com/presidents/article-9116907
1810s
Context: We may say with truth and meaning that governments are more or less republican, as they have more or less of the element of popular election and control in their composition; and believing, as I do, that the mass of the citizens is the safest depository of their own rights, and especially, that the evils flowing from the duperies of the people are less injurious than those from the egoism of their agents, I am a friend to that composition of government which has in it the most of this ingredient. And I sincerely believe, with you, that banking establishments are more dangerous than standing armies; and that the principle of spending money to be paid by posterity, under the name of funding, is but swindling futurity on a large scale.

Source: The Curse of Chalion

Letter to Arthur Griggs (June 22, 1920).

Source: Morals and Dogma of the Ancient and Accepted Scottish Rite of Freemasonry (1871), Ch. III : The Master, p. 70
Context: A war for a great principle ennobles a nation. A war for commercial supremacy, upon some shallow pretext, is despicable, and more than aught else demonstrates to what immeasurable depths of baseness men and nations can descend. Commercial greed values the lives of men no more than it values the lives of ants. The slave-trade is as acceptable to a people enthralled by that greed, as the trade in ivory or spices, if the profits are as large.

Source: A Thousand Plateaus: Capitalism and Schizophrenia