I am glad that Logica Universalis has been chosen for a Memorial Special Issue devoted to Jaakko Hintikka. It makes sense for many reasons. He himself published a paper with a very nice title in our journal: Which Mathematical Logic is the Logic of Mathematics?, LU, Volume 6 (2012)
I met Jaakko in different places at different times, here a few I remember:
- My first meeting with him was at the 7th International Logica Meeting that took place at Liblice castle in June 1993 in Czech republic, he was there jointly with his wife Merril.
- He was the secret speaker of the 3rd UNILOG that took place in Estoril, near Lisbon in 2010. He came from Boston despite the erruption of Eyjafjallajökull entailing the largest air-traffic shut-down since World War II, proving he was not afraid even of Volcanos.