Abstract
The talk maps the manifestations of the "principle of reference" (the assumption that it is impossible to refer to entities that do not have any ontological status) in early analytic philosophy and in high scholasticism. The author shows how Duns Scotus rejects the principle and how even mere envisaging this alternative requires a reconsideration of the common distinction between actualism and possibilism.
It appears that one has to distinguish two kinds of actualism-possibilim distinction: a metaphysical one and a semantical one.