In the past 40 years, no other justice has gone an entire term, much less five, without speaking at least once during arguments, according to Timothy R. Johnson, a professor of political science at the University of Minnesota. Justice Thomas’s epic silence on the bench is just one part of his enigmatic and contradictory persona. He is guarded in public but gregarious in private. He avoids elite universities but speaks frequently to students at regional and religious schools. In those settings, he rarely dwells on legal topics but is happy to discuss a favorite movie, like “Saving Private Ryan.”…

He has said, for instance, that he is self-conscious about the way he speaks. In his memoir, “My Grandfather’s Son,” he wrote that he had been teased about the dialect he grew up speaking in rural Georgia. He never asked questions in college or law school, he wrote, and he was intimidated by some fellow students.

Elsewhere, he has said that he is silent out of simple courtesy.

“If I invite you to argue your case, I should at least listen to you,” he told a bar association in Richmond, Va., in 2000.