Obsta principiis, nip the shoots of arbitrary power in the bud, is the only maxim which can ever preserve the liberties of any people. When the people give way, their deceivers, betrayers, and destroyers press upon them so fast, that there is no resisting afterwards.

John Adams (1735-1826) American lawyer, Founding Father, statesman, US President (1797-1801)

Essay (1775-02-06), “Novanglus,” No. 3, Boston Gazette
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The Latin means to resist the first approaches or encroachments of a problem.

This series of essays was written by Adams under the pseudonym of "Novanglus" (Latin for "New England") responding to essays from his past friend Daniel Leonard as "Massachusettensis" on colonial leadership and what the proper relationship was between the American colonies and Britain.