“There are never any occasions when you need think yourself safe because you wield the weapons of Fortune; fight with your own! Fortune does not furnish arms against herself; hence men equipped against their foes are unarmed against Fortune herself.”
As quoted in Epistulae morales ad Lucilium by Seneca, Epistle CXIII (trans. R. M. Gummere)
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Posidonius 5
ancient greek philosopher -135–-51 BCRelated quotes

On Lord Castlereagh's use of bribery to pass the Irish Act of Union. Quarterly Review, 111, 1862, p. 204
1860s
Man's Rise to Civilization (1968)
Context: Following the War of 1812, the young United States had no further need for Indian allies against the British, and as a result the fortunes of the Indians declined rapidly. By 1848, twelve new states had been carved out of the Indian's lands, two major and minor Indian wars had been fought, and group after group of Indians had been herded westward, on forced marches, across the Mississippi River.

“There are some weapons you can't protect yourself against.”
Source: Mercy

“Fortune does not change men, it unmasks them.”
Reported in "The Viking Book of Aphorisms: A Personal Selection" By Wystan Hugh Auden, Louis Kronenberger (1981)

“It is very fortunate that kings cannot err. Hence their contradictions never perplex us.”
The Man Who Laughs (1869)