Quotation: "Eternal vigilance is the price of liberty."
Sources consulted: (searching on the phrase "eternal vigilance")
Earliest known appearance in print: 1817 (as "eternal vigilance is the price we pay for liberty")
Earliest known appearance in print, attributed to Jefferson: 1834 ("Mr. Jefferson, the great apostle of human rights, has told us, that 'the price of Liberty is eternal vigilance.'")
Other attributions: Patrick Henry, Junius, Wendell Phillips
Status: We currently have no evidence to confirm that Thomas Jefferson ever said or wrote, "Eternal vigilance is the price of liberty" or any of its variants.
Comments: This quotation was well-known in the nineteenth century, and was in fact used by a number of famous figures, including Frederick Douglass, James Buchanan, and William Henry Harrison. It can be traced back, ultimately, to John Philpot Curran's statement, "The condition upon which God hath given liberty to man is eternal vigilance; which condition if he break, servitude is at once the consequence of his crime and the punishment of his guilt." Curran was still being directly quoted (more or less accurately) and credited with the quote in American newspapers in the early nineteenth century, but before long the quote was being used without Curran's name, and was being shortened to its more well-known modern form.
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