The arc of the moral universe is long, but it bends toward justice.

1. 1853Before it · credited to Theodore ParkerTheodore Parker develops the metaphor of a long moral universe whose curve he discerns through conscience, bending toward justice.Theodore Parker, Ten Sermons of Religion (Boston: Crosby, Nichols and Company, 1853), “Of Justice and the Conscience.”, pp. 84–85. Checked on another researcher’s citation, not seen first-hand. Source
2. 1918Earliest found · credited to Theodore ParkerThe earliest exact concise wording located by Quote Investigator appears in an anthology, attributed to Theodore Parker; this is not a claim that the wording originated in 1918.The arc of the moral universe is long, but it bends toward justice.John Haynes Holmes, Harvey Dee Brown, Helen Edmunds Redding, and Theodora Goldsmith, Readings from Great Authors (New York: Dodd, Mead and Company, 1918), section “Justice: Theodore Parker.”, p. 18. Checked on another researcher’s citation, not seen first-hand. Source
3. 2 September 1957Spread · credited to Martin Luther King Jr.King uses the same concise sentence in his Highlander address, decades after its documented print appearance.The arc of the moral universe is long, but it bends toward justice.Martin Luther King, Jr., “A Look to the Future,” Highlander Folk School, 2 September 1957, King Papers transcript. Checked in a full-text transcription. Source

At Highlander’s anniversary meeting, King surveys slavery, segregation and the prospect of integration, then calls for sustained nonviolent struggle. Near the conclusion he urges his audience not to despair and says that the struggle for justice has cosmic companionship. The sentence is followed by literary affirmations that falsehood and injustice will not finally prevail.

He affirms a moral order that sustains hope in the long struggle for justice, even when immediate events appear discouraging.

King really used the sentence, but did not originate its wording: an identical concise form was printed before his birth. Nor does the surrounding speech promise progress without human action; it repeatedly demands passionate, unrelenting and nonviolent struggle.

Hope, Society, Politics, Morality, Change, Wisdom

• I believe that unarmed truth and unconditional love will have the final word in reality.
• Trust thyself: every heart vibrates to that iron string. Ralph Waldo Emerson
• Human potential, though not always apparent, is there waiting to be discovered and invited forth. (paraphrase) William W. Purkey
• And so rock bottom became the solid foundation on which I rebuilt my life. J. K. Rowling
• In the middle of winter, I was finally learning that there was an invincible summer within me. Albert Camus

• quoteinvestigator.com/2012/11/15/arc-of-universe

Martin Luther King Jr., Martin Luther King, Jr., “A Look to the Future,” address delivered at Highlander Folk School’s Twenty-fifth Anniversary Meeting, Monteagle, Tennessee, 2 September 1957; King Papers, Stanford University, transcript from an audio recording. Checked at Quotogeny, https://quotogeny.com/q/arc-of-the-moral-universe/ (24 October 2026).

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