 In this special case, Basic Law V asserts: the extension of the concept \(F\) is identical to the extension of the concept \(G\) if and only if all and only the objects that fall under \(F\) fall under \(G\) (i.e., if and only if the concepts \(F\) and \(G\) are materially equivalent). In more modern guise, Frege’s Basic Law V asserts that the set of \(F\)s is identical to the set of \(G\)s if and only if \(F\) and \(G\) are materially equivalent: