Abstract
I argue that "obligation" is a referential notion, flowing from actual or potential relationships. Applied to future persons, our relationship with them is established by virtue of the significant effects that our acts will have on them, and this in turn provides the basis of our obligation to them. Referential problems arise particularly in the types of cases where alternative acts bring different people into existence, for here there is no clear referent of the obligation. In such cases a theistic model has an advantage by delineating lines of obligation through God.