Paper on Weiss and Bertalanffy presented at the ISSS 2006 50th annual meeting Stefan Blachfellner 20 years ago At the ISSS 2006 (50th Annual Meeting) a paper by Drack and Apfalter was presented: Is Paul Weiss’ and Ludwig von Bertalanffy’s System Thinking still valid today? Related posts Vienna 2011 | Ludwig von Bertalanffy 110 Aniversary by Stefan Blachfellner 14 years ago ISSS2017 Vienna. A Review! by Stefan Blachfellner 9 years ago Heinz von Foerster Symposium by Stefan Blachfellner 19 years ago