descriptive claim
Before Lean, Thomas Hales used HOL Light and Isabelle to formalize this work, marking a milestone.
Unresolved speaker · Mathematics Just Changed Forever — Kevin Hartnett · 26 Oct 2026
In their words
The transcript segments this claim was taken from
“This all happened before Lean. He used Holight and Isabelle to do this work. But it was a milestone.”6:08Report a misattribution
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0.75importance to the conversation
0.88confidence the claim was read correctly