Opinion | The Sidney Awards

In the middle of the 18th century, Francis Williams was almost certainly the most famous Black man in the English-speaking world.He was a scholar, a scientist and a gentleman, educated at Cambridge but living in Jamaica.

After his death in 1762, defenders of slavery set out to prove that no person like Williams — both Black and brilliant — could possibly exist.In 1774 Edward Long wrote an account of Williams’s life that was little more than a racist diatribe, denigrating his many abilities.

And for centuries, that’s where things stood.But a portrait of Williams remains.In it he is standing in a library or study surrounded by books, his hand resting on some big, fat volume.

To his right is an open window showing a strange sky.Fara Dabhoiwala, the author of “What Is Free Speech?” began examining that painting, using high-resolution image technology, to see what Williams was trying to tell us, posing in that manner.Dabhoiwala describes his quest in a slow-building but ultimately unforgettable essay in The London Review of Books.

Through his sleuthing, he discovers that on the study’s bookshelf there is a copy of Samuel Johnson’s dictionary, one of the more expensive scholarly and prestigious books of the time.Williams is telling us: You are looking at a man of letters.That’s not all.

As a young man, Williams knew several of the greatest physicists of the age, including Edmund Halley, a collaborator with Isaac Newton and the discoverer of Halley’s comet.In the portrait, it turns out that Williams’s hand is resting on Newton’s “Principia,” open to page 521.

That page contains representations of complex calculations about the orbit of comets.Dabhoiwala establishes that outside the window is an image of a comet streaking across the sky.

Williams is saying: This is who I am, a Black man operating on the cutting edge of science, a living refutation of the pervasive racism of the day.Dabhoiwala’s essay, “A Man of Parts and Learning,” i...