 Arguably, it is these differences over the appropriate strategy for determining narrow contents that are the most important differences between rival views of narrow content. Although we have considered several different views about the sort of semantic entities narrow contents might be, all these views, with the exception of conceptual role semantics, are close cousins of the view that narrow contents are sets of centered worlds. The most substantive differences between rival views concern how to determine which centered worlds are included in the narrow content of a particular state of a particular subject.