By Ben Cohen

Imagine how mortifying it would be if anyone ever read your diary.

Now imagine it's a diary from a stressful period of your life and it's being read in a courthouse and people all over the world are paying attention because you're being sued by the richest man on the planet and the future of your company might just depend on your private thoughts that have suddenly become much too public.

It was also unimaginable for Greg Brockman.

But over two excruciating days this week, journal entries from OpenAI's president and co-founder were entered as exhibits in the trial captivating Silicon Valley.

Elon Musk's lawsuit against Brockman and Sam Altman has shaken loose a trove of evidence, offering a peek inside the minds of the people who have spent the past decade building artificial intelligence. We have read their unvarnished emails, dishy texts, notes from meetings that determined OpenAI's future -- and one deeply human journal.

In any other part of civilized society, rifling through someone else's diary is considered an outrageous invasion of privacy. In a court of law, it's called discovery.

While the discovery process always produces surprising documents, the idea of a tech executive keeping a journal was especially shocking. Nobody knew it existed until January, when Musk's lawyers revealed that they had Brockman's journal -- hundreds of pages of material -- and they had grilled him about specific passages. OpenAI has said those snippets were cherry-picked and presented out of context, but the judge still quoted them in her ruling that cleared the way for a trial.

As the characters in this soap opera have taken the stand, Brockman's diary has emerged as a star witness.

In case you haven't followed every twist of this legal saga, here's how we got here. Musk accused Brockman and Altman of " stealing a charity," convincing him to bankroll OpenAI as a nonprofit only to flip it into a for-profit company. He wants to remove them from leadership roles, along with billions in damages and the unwinding of OpenAI's conversion, any of which could warp the entire industry. That outcome is unlikely, according to prediction markets. The odds favor OpenAI, which argues that Musk supported the plan, left when he wasn't given control and sued for competitive reasons now that he has a rival lab.

Brockman's journal entries were dissected in the courtroom and broadcast to strangers around the world because they're a window into what OpenAI's leaders were thinking during that period.

This one from August 2017 shows Brockman weighing money against a mission to benefit humanity:

In this entry from September, his stream-of-consciousness writing about the Musk situation reads like ChatGPT reasoning through a messy problem:

In November, before and after a pivotal meeting with Musk, Brockman wrote the entry that would become Exhibit 161:

As you can see, Brockman's writing is full of uncertainty, ambition, introspection, raw emotion, self-awareness and self-doubt. You don't need an AI detector to know it's entirely the work of a human.

He described his style as "chain of thought," which is also how AI models think. To the rest of us, it's simply thinking out loud. The pages capture the inner thoughts of someone who found himself at the center of history, as if Oppenheimer grabbed a pen and bared his soul during the Manhattan Project. And they obviously weren't meant to be read.

"What audience did you write your journal for?" OpenAI's lawyer asked him.

"Myself," Brockman replied.

While OpenAI lawyers refer to his notes as a journal, Musk's lawyers have repeatedly called it a diary, as in: "Let me go back to your diary -- your journal, excuse me."

Whatever you call it, Brockman has been keeping one since 2010, back when he was deciding what to study in college. When he decided to drop out, he became one of the first employees at Stripe and eventually started OpenAI with Musk and Altman. Along the way, he learned that he processes his thoughts by typing them on his laptop.

So as he built a career and then a company, Brockman kept a journal the whole time.

"It's something I used in my personal life and my professional life," he testified, "as I was thinking through decisions or when very important things happened."

The brawl for control of OpenAI was one of those very important things. In his writing from 2017, he's clearly wrestling with his decisions and trying to sort through how he feels -- and what he wants. It might just be the most relatable part in this billionaire feud for AI supremacy.

For tech insiders, it's also the part that does not compute.

"He was journal-maxxing his plans," Jason Calacanis said on the "All-In" podcast.

"It's not just journal-maxxing," co-host David Sacks added. "It's discovery-maxxing."

"I love the guy, but what the f -- is he thinking?" David Friedberg chimed in. "I don't know anyone that has a diary. I've never heard of this."

But he's not alone in keeping detailed written records and committing his stray thoughts to paper -- or pixels. There's actually a long history of powerful executives spilling their feelings in a place where they don't expect anyone to find them.

The legendary Intel chief executive Andy Grove kept a journal from the month his company was founded in 1968. It might seem odd that the man who wrote a book called "Only the Paranoid Survive" was also writing in a diary. In fact, it was one of his survival tactics. Grove dumped his thoughts into marble composition notebooks to sharpen his thinking, said Richard S. Tedlow, a Harvard Business School professor emeritus who was granted access to those journals.

Handing them over to biographers is one way that the diaries of industry titans become public. The other way is when those journals are pried from their hands.

In the case of convicted FTX fraudster Sam Bankman-Fried, federal prosecutors obtained his top lieutenant's journal and her frequently updated list called "Things Sam Is Freaking Out About." They also secured a list that Bankman-Fried wrote to himself, which began: "These are all random probably bad ideas that aren't vetted; CONFIDENTIAL." It might as well have been ripped from a diary.

It's not clear how Brockman's actual diary will play with the jury or judge. Musk's attorney tried to use it against him during the trial, while OpenAI's lawyer asked one question that his writing couldn't answer: How did it feel to have everyone reading his journal?

"Well, it's very painful," he said.

"But," he added, "there's nothing in there that I'm ashamed of."

Brockman also said that he stopped writing about OpenAI in his journal in 2023. He didn't say why. But these days, there's another way to keep a diary -- and it's one he couldn't have imagined when he started typing into his.

Now he can just type into ChatGPT.

Write to Ben Cohen at ben.cohen@wsj.com

(END) Dow Jones Newswires

May 08, 2026 21:00 ET (01:00 GMT)

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