Wall Street was stunned Monday when Treasury Secretary Scott Bessent was taken to task by one of his friends and mentors: legendary hedge-fund investor Stanley Druckenmiller.

In an opinion article for The Wall Street Journal, Druckenmiller sharply criticized Bessent's move to intervene in the U.S. bond market, saying that stepping up government buybacks to bring down yields was a mistake. The Journal's opinion pages operate independently from the newspaper's newsroom.

Druckenmiller said there was no dysfunction in the market that would warrant such a move and that high inflation and runaway federal debt were among the forces driving up yields.

Investors' attention soon shifted from shock at Druckenmiller's broadside against his mentee to the question of whether he used artificial intelligence to write the piece. Some social-media observers said they thought that was the case after running it through AI- detection programs.

In an interview, Druckenmiller said that he did use AI to help produce the piece.

"I was a B student in English, but an A+ in economics," he said. "These are my ideas and I've been speaking about them for over 15 years, as anyone who knows me knows. Would I prefer that I was a great writer? Yes, but that's not who I am."

Druckenmiller said he and his colleagues in his family office use all the major AI tools-Anthropic's Claude, OpenAI's ChatGPT, Google's Gemini and Perplexity-for their work, including their writing. He sees it as akin to relying on a speechwriter or a calculator.

"At 73 I'm kind of proud of using it," he said. He declined to say which AI tool helped him compose the Journal piece, which he wrote over the weekend while on vacation with his grandchildren.

"AI is a fact of modern life," said Paul Gigot, the Journal's editorial page editor, in a statement. "The question for us is whether what we publish from contributors reflects an author's original argument, and if the author has the standing and credibility to make it. In Stan Druckenmiller's case, we have had a relationship with him for many years, and nobody can doubt that his op-ed is his genuine opinion."

Notus, the Washington, D.C., news startup owned by Robert Allbritton, earlier reported on Druckenmiller's use of AI.

Druckenmiller's process in crafting the op-ed drives home how prevalent AI tools have become in executives' everyday lives and public messaging. "There's no one I know who doesn't use AI" for writing, he said.

Whether and how to disclose use of AI is a point of contention among writers, editors and publications. Responding to a glut of what it saw as low-quality, AI-generated content from aspiring thought leaders, LinkedIn recently introduced a "seems like AI slop" tag users can click for posts that they find questionable.

Earlier this month the Financial Times attached a note to an opinion piece by a Harvard professor after it was published, disclosing that the professor had used AI and that its code of conduct prohibits such activity. Authors have seen their books pulled or publication deals scrapped amid allegations of AI usage, even when they have denied a reliance on the technology.

Druckenmiller said he wrote the op-ed after a tumultuous week in the bond market. Last Wednesday, the Treasury Department said it would at least double buybacks for long-term bonds.

The announcement led to an immediate sharp drop in yields. The impact seemed to diminish afterward, with yields rebounding at the end of last week. But they have dropped again this week alongside a retreat in oil prices, putting the yield on the 10-year U.S. Treasury note back below where it was before the announcement on Wednesday.

Early Tuesday, internet sleuths started circulating their takes on the provenance of the Druckenmiller piece. Haseeb Qureshi, a venture-capital investor focused on crypto, posted a screenshot on X showing that an AI-detection program determined the article was likely AI-generated.

"If you read the text, it's glaringly obvious," Qureshi said in the post.

Druckenmiller said he wasn't ashamed of using AI-but was a little stung by the reaction.

"The only embarrassing thing is how many people reached out and told me how much better written this was than normal," he said.