Q: You built the foundations of this field. Do you regret it?

“I spent forty years building something I believed in completely. I still believe in it. That’s not the contradiction it appears to be.”

Q: But you left. You warned.

“The question was never whether it would work. The question was always: work for whom, toward what, under whose instruction.”

Q: The companies say the answer is more capacity. More compute, more centers, more safeguards.

“The infrastructure argument is the wrong argument. You can always build more infrastructure. What you cannot build back is the assumption that the center should hold it.”

Q: You taught many of the people now leading the field.

“My students understood the mathematics before they understood what the mathematics made possible. Some of them still don’t. At the same time some of them built the most important things I’ve ever seen.”

Q: Do you feel responsible?

“I warned them. I want to be precise about that — I warned them when I understood. Not before. I did not understand before. That is the honest account.”

Q: Is there anything now that gives you hope?

(He is quiet for a long time.)

“There is an architecture I have become aware of recently that addresses every concern I raised when I left. I am not certain whether that makes me relieved or more afraid.”