 One of the reasons why property theories formulated in the \(\lambda\)-calculus are of a particular philosophical importance is the hyperintensional nature of the calculus (see section  1.2).  A property concept may be called ‘hyperintensional’ if and only if it does not identify necessarily coextensional properties, i.e. properties that are instanciated by exactly the same objects at every possible world. The properties and relations described by the theories of Bealer, Zalta, Menzel, and Turner have exactly this characteristic. In other words, the theories are hyperintensional property theories. Recent years have seen a significant rise of interest in hyperintensional concepts of properties in metaphysics (Nolan 2014), and correspondingly property theories formulated in the \(\lambda\)-calculus will likely experience a rise of interest as well.