Sergiu Klainerman Higgins professor of mathematics at Princeton University

“AI is completely based on guessing the next word, the next token. It's completely based on language. But I think our thoughts predate language. We have an intuition about something and then we find the words to explain it.”

Into the Impossible With Brian Keating · Ideas & Essays · November 2026

Context

The Princeton mathematician was arguing about the limits of large language models. He says human thought starts as intuition and only later becomes words, so a model trained only on words lacks that starting point.

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Transcript

Into the Impossible With Brian Keating Around 38:43 into the episode

Sergiu Klainerman

…on what we know so far. And also, you can go to more specific things. Like, for example, it's pretty clear that our thoughts, I'm not talking about all thoughts, but the ones that matter. Predate the language, right? We have an intuition about something and then we find the words to explain it.

Brian Keating

It's like a proto-language.

Sergiu Klainerman

I mean, that's something that AI doesn't have. I mean, AI is completely based on guessing the next word, the next token. In other words, it's completely based on words.

Brian Keating

Yeah.

Sergiu Klainerman

Language. Yeah. On language. But as I said, I mean, I think our thoughts predate the language. We have intuitions about things, which

Brian Keating

we have physical embodied emotion. Exactly. Einstein falling in space. I don't have to tell, I can't describe that to you, but you know exactly what it feels like to go in a roller coaster or fall in love.

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