The i* community has raised several main dialects and dozens of variations in the definition of the i* language. Differences may be found related not just to the representation of new concepts but to the very core of the i* language. In previous work we have tackled this issue mainly from a syntactic point of view, using metamodels and syntactic-based model interoperability frameworks. In this paper, we go one step beyond and consider the use of foundational ontologies in general, and UFO in particular, as a way to clarify the meaning of core i* constructs and as the basis to propose a normative definition. We focus here on one of the most characteristics i* constructs, namely means-end links.