United we stand, divided we fall.

Aesop (620?-560? BC) Legendary Greek storyteller

Fables [Aesopica], “The Four Oxen and the Lion” (6th C BC) [tr. Jacobs (1894)]
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Alternate translation: "The quarrels of friends are the opportunities of foes." [tr. James (1848), "The Lion and the Bulls"]

Alternate translation: "Union is strength." [tr. Townsend (1887), "The Lion and the Three Bulls"]