This is very sad news, and he will be deeply missed. Everyone from the University of Wales will certainly remember Ronnie as a larger-than-life character. After doing a Masters in knot theory with Ronnie, I started a PhD with him in algebraic topology. Although I soon decided that I was better suited to categorical logic, inverse semigroups, and theoretical computing, he was keen to support me in whatever direction I took. He made it clear that he had no hard feelings towards me swapping subject & supervisor, and went out of his way to introduce me to people in my chosen fields. Somewhat ironically, I later ended up using exactly the topics he had been teaching me about (topology, homotopy, and of course higher-dimensional groupoids) in my new fields anyway. I suspect that this wasn't entirely unexpected to him. As well as his mathematical achievements, which are many, we should also remember his work in fighting against the closure of the Mathematics Dept. at Bangor. Peter On 12/7/24 19:14, Timothy Porter wrote: I have been asked by his son Marcus to inform his friends on the Categories mailing list that Ronnie Brown who was for many years professor at the University College of North Wales (later renamed the University of Bangor) died yesterday at his home in Deganwy. Please share this information with others who may have known Ronnie. Thanks, Tim Porter. 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>