 MD/CD normativism aims at answering “foundational” questions and providing metaphysical explanation: In virtue of what do linguistic expressions/intentional states have meaning/content? Metaphysical explanation of \(X\) by means of \(Y\) requires that \(X\) at least supervenes upon  \(Y\).[2]  Supervenience relations involve three elements: a set of supervenient entities \(S_E\), a set of entities forming the supervenience base \(S_B\), and a principle according to which what is in \(S_B\) determines what is in \(S_E\) (a function from \(S_B\) to \(S_E)\). Whether supervenience suffices for metaphysical explanation or not, an explanation will therefore not be complete unless the principle of determination is  specified.[3]  When it comes to meaning, this is arguably one of the most important lessons of Wittgenstein’s so-called rule-following considerations; as long as only the supervenience base is specified, its elements can be mapped onto meanings in any old way, thus leaving meaning completely indeterminate (cf. Pagin 2002, Glüer  2018).[4]