Krister Segerberg (1936-2025)
Krister Segerberg, professor emeritus of philosophy at Uppsala University, has died.

Professor Segerberg was known for his work in logic, particularly modal logic. You can learn more about his writings here and here.
He joined the Uppsala faculty as Chair Professor of Theoretical Philosophy in 1990, where he worked until his retirement in 2001. Prior to that he held positions at the University of Auckland in New Zealand and Åbo Akademi University in Finland. He earned two PhDs—one from Stanford University and one from Uppsala. His undergraduate degree was from Columbia University.
A memorial notice has been posted at the Uppsala Department of Philosophy website, along with some personal notes. Those with their own remembrances to share there may email them to Matti Eklund as well as post them in the comments here.
(via Matti Eklund)
A great logician, and many of his good results have not been put into textbooks yet.