In life, the late Rev. Dr. Martin Luther King, Jr. was notorious for borrowing without attribution, and the Obama White House has kept the King tradition of appropriation marching on, in an Oval Office rug in which King is credited with a line borrowed from Transcendentalist minister Theodore Parker.

Washington Post:

President Obama’s new presidential rug seemed beyond reproach, with quotations from Abraham Lincoln, Theodore Roosevelt, Franklin Roosevelt, John F. Kennedy and the Rev. Martin Luther King Jr. woven along its curved edge.

“The arc of the moral universe is long, but it bends toward justice.” According media reports, this quote keeping Obama company on his wheat-colored carpet is from King.

Except it’s not a King quote. The words belong to a long-gone Bostonian champion of social progress. His roots in the republic ran so deep that his grandfather commanded the Minutemen at the Battle of Lexington.

For the record, Theodore Parker is your man, President Obama. Unless you’re fascinated by antebellum American reformers, you may not know of the lyrically gifted Parker, an abolitionist, Unitarian minister and Transcendentalist thinker who foresaw the end of slavery, though he did not live to see emancipation. He died at age 49 in 1860, on the eve of the Civil War.

A century later, during the civil rights movement, King, an admirer of Parker, quoted the Bostonian’s lofty prophecy during marches and speeches. Often he’d ask in a refrain, “How long? Not long.” He would finish in a flourish: “Not long, because the arc of the moral universe is long, but it bends toward justice.”

King made no secret of the author of this idea. As a Baptist preacher on the front lines of racial justice, he regarded Parker, a religious leader, as a kindred spirit.

Yet somehow a mistake was made and magnified in our culture to the point that a New England antebellum abolitionist’s words have been enshrined in the Oval Office while attributed to a major 20th-century figure.