Academia Europaea had its 25th Anniversary Conference in Wrocław, Poland, 16–19 September 2013. It is a tradition at the annual conferences that one session is devoted to a field of research where the host country has made exceptional achievements. In Wroclaw, the choice fell on the intersection between philosophy and logic, where the Polish contributions have shaped the international development of the field for more than 100 years.

This Polish development was carried out by a large number of teachers and students through several generations, starting with Kazimierz Twardowski (1866–1938) when he returned to Poland in 1895 after having earned his PhD and his habilitation with Franz Brentano and Robert Zimmerman in Vienna.

Twardowski’s students and their students and generations of students after them form a tradition that has been called the Lvov-Warsaw school, named for the two universities where their influence was particularly strong. However, the tradition also spread to many other universities in Poland and abroad. During the Second World War many members of the school were killed by the Nazis and others fled, and the cold war led to emigration to countries with better conditions for research. However, the school survived and continues to make important contributions.

The word ‘school’ is misleading. This word is often applied to a group of people who subscribe to the same or very similar views. In some intellectual cultures it is regarded as an honor to have founded a school and have many followers. This often leads to favoring members of one’s own school when it comes to appointments and honors.

In countries where the senior scholars or scientists have a considerable influence on who is going to succeed them when they retire, this attitude often has destructive consequences. Young people tend to emphasize their agreement with the persons in power, and those who are independent have to remain in subordinate positions or find employment somewhere else.

This was not the case with the Lvov-Warsaw school. The members had very different views and worked on a wide range of issues. What united them, was an emphasis on arguments and on clarity in thought and language. Both in teaching and appointments they favored quality and originality. This attracted good students and, together with excellent teaching and advising, it led to an impressive recruiting of young people who became leaders in their field and made Poland a principal country in the area where mathematics and philosophy meet.

In this issue of European Review, the history and main contributions of this development is outlined, with chapters on the main figures, their work and impact: Twardowski, Łukasiewicz, Leśniewski, Tarski, and Mostowski. A large number of other contributors are mentioned wherever appropriate.

I am indebted to Jan Woleński and Peter Simons for valuable advice in the selection of contributors, and to the contributors for their willingness to participate. We are all grateful to the participants in this session in Wroclaw for their valuable comments and suggestions.