The aim of the paper is to bring back Jerzy Łoś’s great contribution to the area of epistemic and temporal logic. Although his mathematical achievements are widely recognized and appreciated around the world, his early works are still very little-known, despite their pioneering nature. The authors also give an account of current research and results inspired by Łoś’s legacy.The aim of the paper is to bring back Jerzy Łoś’s great contribution to the area of epistemic and temporal logic. Although his mathematical achievements are widely recognized and appreciated around the world, his early works are still very little-known, despite their pioneering nature. The authors also give an account of current research and results inspired by Łoś’s legacy
