Dear Jaap and Categories, I’m deeply saddened by this news, even though we’ve known for some time now that it was probably going to happen soon. Thomas was a great mathematician and a great friend. I met him 30 years ago at the CT in Tours, and we hit it off immediately and remained friends ever since. I visited him in Darmstadt many times, slept on his couch, collaborated on papers, and, in later years, shared students and postdocs. I learned a great deal from him about how to combine type theory and category theory into a single, beautiful subject with fascinating different aspects. He knew about univalence before it was called that, and introduced the Kan simplicial set model of type theory at the workshop in Uppsala in 2006. He also stood by me when I needed it, without regard to his own interests. He will be greatly missed. Steve On Jan 3, 2025, at 4:04 AM, Oosten, J. van (Jaap) <J.vanOosten@uu.nl> wrote: I just received information that Thomas Streicher passed away yesterday. Thomas fell ill last September, when he could not attend Pino Rosolini's retirement party due to pneumonia; then it turned out he has metastases in the lungs from a pancreatic cancer. After several chemo treatments his situation suddenly worsened, and yesterday he died, peacefully, without pain. Thomas was 66 years old. In Thomas, we mourn a logician and category theorist of exceptional calibre. Let me just recall that in 2011, during an Oberwolfach meeting, Vladimir Voevodsky praised Thomas' work on type theory as a paradigm of precision. But I personally mourn a friend. A warm person with many interests. I wish strength to his wife Eva, and his family. Jaap van Oosten You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.ashx?source=EscalatedMessage&action=files&GuestId=6bf90c14-94d1-45b7-a0b5-9dd447734d27> | Leave group<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.ashx?source=EscalatedMessage&action=leave&GuestId=6bf90c14-94d1-45b7-a0b5-9dd447734d27> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>