In memoriam: Jan Małuszyński

Our friend, colleague and mentor Jan Małuszyński, age 79, passed away in his home on June 27th, 2020, after an extended battle with cancer. Our thoughts go, in particular, to Jan’s wife Gizela and their children Ania and Chris and four grandchildren.

Jan was born 1941 during World War 2 in Lwów, at the time in Poland, under Soviet occupation, now Lviv in Ukraine. He studied in Gliwice, Warsaw and Moscow and obtained master’s degrees in electronics and mathematics. His PhD in 1973 at the Institute of Mathematics, Polish Academy of Sciences, under supervision of Prof. Zdzisław Pawlak, addressed context-free parsing. Jan migrated to Sweden in 1982 after martial law was introduced in Poland. He became professor in programming theory at Linköping University where he remained until his retirement in 2008 and then continued as professor emeritus for several years after that.

Jan made contributions to many subareas of programming theory. His research was characterized by mathematical precision striving for simple and well understood principles and always keeping in mind the connection between theoretical foundations and the practice. His early research involved grammatical formalisms such as two-level and attribute grammars. He was early involved in declarative programming languages, in particular logic programming. While logic programming remained his main research focus he also developed an interest in constraint programming and formalisms for knowledge representation and reasoning on the semantic web.

Jan authored numerous research papers with more than 40 co-authors. This illustrates his ability to connect and collaborate with other researchers. He was the co-author of two monographs and editor of a large number of conference proceedings and anthologies. He was a frequent participant at logic programming venues with a contribution already at the first ICLP in Marseille 1982 comparing Prolog and two-level grammars. He was frequently appearing in program committees and he chaired the International Logic Programming Symposium (ILPS) in Port Jefferson, NY, 1997. He was instrumental in launching two European projects (DiSCiPl Esprit Project – Debugging systems for constraint programming in 1996, and network of excellence REWERSE – Reasoning on the Web with Rules and Semantics in 2004) and a series of PLILP conferences (International Symposia on Programming Language Implementation and Logic — again illustrating Jan’s ability to connect with others and to build networks. Other fields where Jan made significant contributions include so-called directional types, amalgamation of logic and functional programming, verification of program correctness and algorithmic debugging. Jan in some sense closed the circle when he started to investigate rough sets in the early 2000’s — a concept conceived by Jan’s adviser Prof. Pawlak.

At Linköping University Jan established and led the logic programming laboratory where Jan advised seven graduates to their PhD-degrees. It was a creative environment also visited by numerous international researchers for short as well as extended stays. Jan’s leadership was characterized by generosity and trust. He mentored the junior group members to become independent researchers and preferred to promote others rather than boosting his own achievements.

On behalf of former students and colleagues we would like to express our great gratitude to Jan and his legacy. A funeral service is scheduled for mid-September in Warsaw, Poland.

Ulf Nilsson & Włodzimierz Drabent