Mario Bunge combined in his ‘Treatise’ specialized philosophical disciplines into a great synthesis on a high technical level. Volume 18 of the Poznan Studies is meant to offer a forum for criticism and debate on this book. Indeed, the thirty two studies on Mario Bunge’s Treatise describe and discuss his work in detail, and Bunge’s thirty two lively replies lead the reader a long way further into his philosophy. The book closes with a short autobiography by Bunge and a chronological list of his more than 350 publications. The ‘Studies on Mario Bunge’s Treatise’ should be of interest not only to philosophers, but also to scientists and technicians with an interest in foundations of their disciplines.