In linguistics, a small clause consists of a subject and its predicate, but lacks an overt expression of tense. Small clauses have the semantic subject-predicate characteristics of a clause, and have some, but not all, the properties of a constituent. Structural analyses of small clauses vary according to whether a flat or layered analysis is pursued. The small clause is related to the phenomena of raising-to-object, exceptional case-marking, accusativus cum infinitivo, and object control. The two main analyses of small clauses originate with Edwin Williams (1975, 1980) and Timothy Stowell (1981). Williams' analysis follows the Theory of Predication, where the "subject" is the "external argument of a maximal projection". In contrast, Stowell's theory follows the Theory of Small Clauses, supported by linguists such as Chomsky, Aarts, and Kitagawa. This theory uses X-bar theory to treat small clauses as constituents. Linguists debate which analysis to pursue, as there is evidence for both sides of the debate. The term "small clause" was coined by Edwin Williams in 1975, who specifically looked at "reduced relatives, adverbial modifier phrases, and gerundive phrases". The following three examples are treated in Williams' 1975 paper as "small clauses", as cited in Balazs 2012. However, not all linguists consider these to be small clauses according to the term's modern definition. The man [ driving the bus ] is Norton's best friend. John decided to leave, [ thinking the party was over ]. [ John's evading his taxes ] infuriates me. The modern definition of a small clause is an [NP XP] in a predicative relationship. This definition was proposed by Edwin Williams in 1980, who introduced the concept of Predication. He proposed that the subject NP and the predicate XP are related via co-indexation, which is made possible by c-command. In Williams' analysis, the [NP XP] of a small clause does not form a constituent. Timothy Stowell in 1981 analyzed the small clause as a constituent, and proposed a structure using X-bar theory.