For decades, Justice Clarence Thomas sat mostly silent on the Supreme Court bench, content to let others debate the controversies of the day. Because Thomas would not argue in public, court watchers had no idea of how he processed arguments beyond his written dissents and concurrences.
Thomas did not spar like Justice Antonin Scalia, the intellectual anchor of the high court's right wing. He didn't mind if his extroverted, opera-loving colleague got a disproportionate share of the glory as long as the court continued in what he considered the right direction.
An avid comic book reader in his youth, Thomas perhaps fancied himself a judicial version of Marvel's Black Bolt, Lord of the Inhumans. A single syllable from Black Bolt's lips could shatter mountains; this forced him to communicate through sign language. He kept his words to himself.