Wessex in classical heraldry and is found on a number of church windows in derived shields such as the Arms of the Collegiate Church of St Peter at Westminster (Westminster Abbey, which was founded by the king). At its greatest extent Wessex encompassed the modern areas of Hampshire, Isle of Wight, Dorset and Wiltshire, as well as the western half of Berkshire and the eastern hilly flank of Somerset. This covers an area of about . The English author Thomas Hardy used a fictionalised Wessex as a setting for many of his novels, adopting his friend William Barnes' term "Wessex" for
S (set theory) sets" or "the class of all ordinals" include sets from all stages of the iterative hierarchy. Hence such collections cannot be formed at any given stage, and thus cannot be sets. This section follows Boolos (1998: 91). The variables "x" and "y" range over sets, while "r", "s", and "t" range over stages. There are three primitive two-place predicates: The axioms below include a defined two-place set-stage predicate, "Bxr", which abbreviates: "Bxr" is read as “set "x" is formed before stage "r".” Identity, denoted by infix ‘=’, does not play the role in S it plays in other set theories,