These insights might help explain why someone as smart as Antonin Scalia seemed so un-self-conscious about his inflammatory rhetoric. He was simply giving voice to those he spent his time with. His world was one that reinforced and never challenged him.

About 10 years ago, I attended a gathering of Canadian judges and lawyers at Cambridge University. Justice Scalia gave his stump speech there about how his Constitution was not “living” but “dead,” with legitimate constitutional interpretation limited to the words and original understanding of the document’s authors. He may or may not have known that in Canada, constitutional interpretation starts from the premise that “the Constitution is a living tree.” In any event, his speech fell flat; rather than greeting his remarks with the appreciative chuckles and applause he usually received, the audience sat on its hands. I remember his disconcerted expression.

Justice Scalia received relatively few opinion assignments in major cases, either from Chief Justice Roberts or Chief Justice William H. Rehnquist, with whom he served for 19 years. The reason was obvious: He refused to compromise, a trait that put him at risk of losing a majority in close cases. I used to wonder why he didn’t value effectiveness over perfection, why he would not rather compromise than lose. But I came to realize that Justice Scalia wasn’t playing the inside game. No matter that he never persuaded a majority of his fellow conservatives on the court to sign up for his brand of originalism.

What mattered was his ability to invoke originalism as a mobilizing tool outside the court, in speeches and in dissenting opinions. The message was that courts have no business recognizing “new” rights. (Except, evidently, new rights of which Justice Scalia approved, such as an unconstrained right for corporations to spend money in politics.) The audience for his dissents, he told Ms. Senior in the New York magazine interview, was law students. The mission he set for himself was cultivating the next generation.

For a long time, he did a good job of addressing the public outside the court’s marble walls. In 2003, his dissenting opinion in the gay rights case Lawrence v. Texas warned that the court’s declaration of constitutional protection for same-sex relationships would lead to protection for same-sex marriage. State after state heeded the warning and enacted same-sex marriage bans.

Ten years later, when he dissented from the court’s overturning of the Defense of Marriage Act in United States v. Windsor, which found that married same-sex couples were entitled to federal benefits, he warned that the decision made the constitutional right to same-sex marriage inevitable. “No one should be fooled; it is just a matter of listening and waiting for the other shoe,” he wrote.

Within a matter of months, federal district judges around the country invoked Justice Scalia’s dissent in striking down same-sex marriage bans. The much less polemical dissent in Windsor by Chief Justice Roberts, describing the decision as a narrow one based on principles of federalism, went uncited.