HELENA RASIOWA, 1917 - 1994

by

W. Bartol, E. Orłowska, A. Skowron

1. Elements of a biography

Helena Rasiowa, mathematician and logician, passed away on August 9, 1994. Her influence on the shape of mathematical logic can hardly be overestimated.

She was born in Vienna on June 20, 1917 to very patriotic Polish parents. As soon as Poland had regained its independence in 1918 after more than a century of partitioned stateless existence, the whole family settled in Warsaw. Helena's father was a high-class railway specialist; his knowledge and experience in the field led him to assume very important positions in the railway administration. The girl, her parents' only child, has had good conditions to grow up physically and mentally. And, indeed, she exhibited many different skills and interests, varying from music, which she was learning at a music school paralelly to her normal studies in a secondary school, to business management, which she studied for more than a semester after completing her secondary education. But finally the most important of her interests, as the future was to prove, took the lead.

In 1938 the time was not very propicious for entering a university. Even if not many in Europe were convinced that war was inevitable, the next year was to prove how mistaken those of the majority were. Rasiowa had to interrupt her studies, for no legal education was possible in Poland after 1939. Many people fled the country or at least they fled the big towns, more subject to German bombardments and terror. So did the Ras family, also because of the fact that most high-ranked administration officials and members of the government were being evacuated towards Romania. The Ras's spent a year in Lvov. After Soviet invasion in September 1939 the town was taken over by the Soviet Union. The life of many Poles became endangered, so eventually the father decided to return to Warsaw.

Life was very restricted in Poland during the Nazi occupation. Nevertheless, there were enough courageous people to organize an underground life, not only for armed conspiracy against the Nazis, but also for the development of all the areas of a nation's life which are vital for its survival, education and, in particular, higher education among them. Thus Helena Rasiowa followed her studies in mathematics, risking her life, as did everybody who dared to conspire during that dark period.

Polish mathematics acquired particular strength in the pre-war years, mainly after the emergence of the Polish School of Mathematics in 1921. The names of Stefan Mazurkiewicz and Waclaw Sierpiński, who were in Warsaw, or those of Stefan Banach and Hugo Steinhaus, who were in Lvov, were well known to mathematicians all over the world. One of the branches which became important at that time besides functional analysis, set theory and topology, was logic, with researchers such as Jan Łukasiewicz, Stanisław Leśniewski, Kazimierz Ajdukiewicz, Alfred Tarski and others.

Rasiowa became strongly influenced by Polish logicians. Still in conspi-racy, she wrote her Master's thesis under the supervision of Jan Ł ukasiewicz and Bolesław Sobociński. History, however, turned against her once more. In 1944 the Warsaw Uprisal broke out and in consequence Warsaw was almost completely destroyed, not only because of warfare, but also because of the systematic destruction which followed the uprisal after it had been squashed down, Rasiowa's thesis has burned toge-ther with the whole house. She herself has survived with her mother in a cellar covered by ruins of the demolished building.

After the war Polish mathematics, as all other areas of life, began to recover its institutions, its moods and its people. Many have been killed, many have died, many have left the country, but those who remained considered their duty the reconstruction of Polish science and universities. One of the important conditions for this reconstruction was to gather all those who could participate in recreating mathematics. Rasiowa had in the meantime accepted a teacher's position in a secondary school. That is where she was discovered by Andrzej Mostowski and brought back to the University. She rewrote her Master's thesis in 1945 and in the next year she started her academic career as an assistant at the University of Warsaw, the institution she remained linked with for the rest of her life.

At this University she prepared and defended her Ph.D. thesis in 1950 (under the guidance of Prof. Andrzej Mostowski). The title of the thesis was Algebraic treatment of the functional calculi of Lewis and Heyting and it pointed to the main field of her future research: algebraic me-thods in logic. In 1956 she made her second academic degree (equivalent to habilitation today) in the Institute of Mathematics of the Polish Academy of Sciences, where between 1954 and 1957 she held a post of Associate Professor jointly with an analogous position at the University, becoming Professor in 1957 and subsequently Full Professor in 1967. For the degree she submitted two papers: Algebraic models of axiomatic theories and Constructive theories, which together formed a thesis named Algebraic models of elementary theories and their applications.

Her interests were not limited to pure research. Always ready to co-operate with others and aware of the importance of a strong mathematical community, she participated in many forms of this community's activities. Since 1964 and till her retirement in 1993 she headed the section of Foundations of Mathematics and later of Mathematical Logic after its creation in 1970. For more than 15 years she was Dean of the Faculty of Mathema-tics, Computer Science and Mechanics (1958-1960, 1962-1966, 1968-1978). Strongly attached to the Polish Mathematical Society, she was its Secretary (1955-1957) and then Vice-President (1958-1959); in the Warsaw division of the Society she was elected President twice (1957-1959 and 1963-1965). In the Association for Symbo-lic Logic she was Council member (1958-1960) and member of the Executive Committee for European Affairs (1972-1977). She also was Alternate Assessor (1972-1975) and Assessor (1975-1979) in the Division of Logic, Methodology and Philosophy of Science of the International Union of History and Philosophy of Sciences. On the other hand, she contributed to the development of mathematics in Poland as a member of the Committee on Mathematics of the Polish Academy of Sciences since 1961 till her very last days and as a member and for 20 years Chairperson of the Group on Education and Research in Mathematics of the Ministry of Science and Higher Education. Since 1972 she was in the Scientific Council of the Institute of Computer Science of the Polish Academy of Sciences, guiding its works as Chairperson in 1972-1983. Last but not least, in the recent years she greatly contributed to the foundation of the Polish Society of Logic and Philosophy of Science.

No description of Rasiowa's activities would be complete without a mention of her deep involvement in the development of research journals she was related to. The most cherished by her, Fundamenta Informaticae , has been established in 1977 mostly due to her efforts and Helena Rasiowa was its Editor-in-Chief until her death. Even when her illness began to took the top of her she never ceased to control the preparation of the consecutive issues of the journal. In particular, she acted as Editor of a special anniversary issue commemorating the publication of the 20th volume of FI in 1994. Moreover, making once more proof of her inexhaustible energy, she was an active Collecting Editor with Studia Logica (since 1974) and Associate Editor with the Journal of Approximate Reasoning since 1986.

Professor Rasiowa educated generations of students and researchers; in particular, she had supervised over 20 Ph.D theses. Her lectures were known all over the world. She had been visiting professor at 14 universities, ranging from Bahia Blanca in Argentina to Moscow in the Soviet Union, passing through Campinas in Brasil, UNAM in Mexico, Rome in Italy and Oxford University in England. In the USA she was hosted by universities such as Princeton, University of Chicago, University of California at Berkeley and the University of North Carolina at Charlotte. Moreover, she gave invited lectures at 46 universities and research establishments abroad, in some of them more than once.

She contributed to mathematical literature with three important books and more than 100 publications. The topics covered by her work include proof theory and deductive logic, algebraic methods in logic and algebras related to logics, classical and non-classical logics, algorithmic and approximation logics, artificial intelligence. She worked on a new monograph till her very last days. The intended title was Algebraic Analysis of Non-Classical First Order Logics.