Professor Russell Ackoff was a great scholar, educator, consultant ... and much more. Intellectual and pragmatic. Logician, mathematician, philosopher, ... , systemist.
He was and excelled at so many things. One could fill an encyclopedia with #s trying to do him justice. The following I want to choose - feeling awkward about it as I am fairly old-fashioned and myself not too at-, dis-, ex-tracted ;-) by what some filters and algos suggest to be of relevance, based on keywords. Nevertheless, today I give in a little because I think Russ had deserved that he catches attention by more than those who watch out for reference to his vast body of contributions anyway.