 On the other side, we have metaphysical approaches, which attempt to pin down the notion of word by inquiring into the metaphysical nature of words. These approaches typically deal with such questions as “what are words?”, “how should words be individuated?”, and “on what conditions two utterances count as utterances of the same word?”. For example, Kaplan (1990, 2011) has proposed to replace the orthodox type-token account of the relation between words and word tokens with a “common currency” view on which words relate to their tokens as continuants relate to stages in four-dimensionalist metaphysics (see the entries on  types and tokens  and  identity over time).  Other contributions to this debate can be found, a.o., in McCulloch (1991), Cappelen (1999), Alward (2005), Hawthorne &amp; Lepore (2011), Sainsbury &amp; Tye (2012), Gasparri (2016), and Irmak (forthcoming).