GERHARD HEINZMANN is professor of Philosophy at the University of Lorraine, founder of the History of science and of philosophy laboratory—Archives Henri Poincaré (UMR 71117), director of the Maison des sciences de l'homme of Lorraine (USR 3261). After studying mathematics, philosophy and Greek philosophy in Heidelberg, he specialized in the philosophy of mathematics and logic. A great mathematician and a great philosopher, he trod a path between rationalism, which bases the explanation of the world on reason and empiricism, which draws knowledge from experimentation. He too also uphold this boundary as it does not separate but brings closer. It is for this very reason that he has accepted to run the Maison des sciences de l’homme in Lorraine.
He realised that the pragmatistic and constructive methods used in the philosophy of mathematics to overcome the difficulties faced also stem from or at least resemble the French tradition around Poincaré, as well as intellectual circles more or less closely associated to it (Gonseth, Piaget, Cavaillès, Beth, Bernays, but also Ajdukiewicz, Brouwer and Weyl). This is especially noticeable if Ludwig Wittgenstein and Nelson Goodman are included as go-betweens for these thinkers and dialogical pragmatism. He decided to institutionalize this connection by having Goodman awarded an honorary doctorate in the framework of the Poincaré Archives in 1997. His research focuses mostly on the use of intuitive and formal elements in mathematics and logic. No one contests that intuition is necessary for invention. However, opinions diverge as to the role intuition may be said to play in the process of understanding and justification in mathematics. Some ascribe a fundamental and irreducible role to it, others just want to exclude it. He is looking for an answer to this dilemma in a pragmatic semantics. It is built upon the works of Kuno Lorenz, mathematical realities cannot be conceived independently from their constructions and the latter are not independent from their language description. Instead of considering the construction and the description of objects as two different procedures of mathematical knowledge, they are regarded as two different aspects of the same process of dialogical construction from a common base of actions taking account of their goals and of the given context. This methodical approach allows him not only to build bridges between analytic philosophy and Poincaré’s work, but also—and this is the most important—to include political and social aspects in theoretical considerations.
