Societal impact: a difficult definition

The missions of research have gradually evolved from a science whose sole purpose is the pursuit of knowledge, to a "useful" science that must demonstrate its impact on society. This demonstration, however, requires a frame of reference and criteria on which to base it. The very definition of the term "societal impact" and what it encompasses can be envisaged in different ways, depending on the answer to a number of questions: What areas can be impacted by research? Does this societal impact encompass all the consequences of research, or is it limited to those expected and defined upstream? Is it linked to the quality of the resulting scientific work? Is it based on a scale of values, or is it "absolute"? Does it only include effects that can be quantified? These are just some of the questions that are currently being discussed, and are summarized below.