 Building on this example, we can see that x is necessarily identical with the sole member of {x} and hence we can arrive at a principle not unlike (ID-NEC). However, even though x is necessarily identical with the sole member of {x}, it is, once again, plausibly not part of the essence of x that x is the sole member of {x} (cf. Fine 1994a: 4–5; see also Fine 1994b for a related discussion of the notion of essence and essential dependence).