Thomas, 70, did not actually say during a conversation before the Supreme Court Historical Society that he was staying on the court. But he made it sound as though rumors of his departure were groundless.
"I have no idea where this stuff comes from," he told David Rubenstein, the financier and philanthropist who interviewed him.
Rubenstein asked Thomas whether it was "enemies putting that out or your fiends putting that out because they wanted you to rest more?"
"I think people just wanted to know what I was going to do," Thomas said, with a laugh. "Since I couldn't figure it out myself."
He said he first heard the rumors from his wife, Ginni, "who gets these alerts."
"She says, 'What is it I don't know?' " Thomas recalled. "I said, "What are you talking about?' She said, 'You're going to retire.' I said, 'Wow, good to know that.' I mean, you have to know every day what's on your schedule."
Thomas, the longest-serving justice and the anchor of the court's conservative wing, has said before that he did not have plans to retire.
"I have no idea where this stuff comes from," Thomas told Rubenstein. "I think one of the things you have to get used to, in this business, in here, is that people can say things about you, and for you, that have nothing to do with you."
Justices are often the subject of retirement rumors, often instigated by those who want a justice to leave when a like-minded president can nominate his or her younger successor. Justices Ruth Bader Ginsburg and Stephen Breyer were on the receiving end of such speculation when President Barack Obama was in office.
Thomas certainly sounded happy on the court, where conservatives have a steady majority. He extravagantly praised his colleagues and called the court "a wonderful place."
He said he and his wife would continue their usual summer practice of traveling the country in a 40-foot motor home. Last summer, they visited 23 states, he said, where sometimes he is recognized. Ginni Thomas usually registers them at the RV parks where they stay, and they take advantage of all the senior discounts available.
"The senior citizens have looked out for themselves," he said.
Asked how he handles the stress of the job, Thomas said he goes to Mass. But he doesn't need a release, he said.
"I actually don't have a lot of stress," he said. "I cause stress."
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