In linguistics, valency or valence is the number and type of arguments controlled by a predicate, content verbs being typical predicates. Valency is related, though not identical, to subcategorization and transitivity, which count only object arguments – valency counts all arguments, including the subject. The linguistic meaning of valency derives from the definition of valency in chemistry. The valency metaphor appeared first in linguistics in Charles Sanders Peirce's essay "The Logic of Relatives" in 1897, and it then surfaced in the works of a number of linguists decades later in the late 1940s and 1950s. Lucien Tesnière is credited most with having established the valency concept in linguistics. A major authority on the valency of the English verbs is Allerton (1982), who made the important distinction between semantic and syntactic valency. Types There are several types of valency: impersonal (= avalent) it rains intransitive (monovalent/monadic) she sleeps transitive (divalent/dyadic) she kicks the ball ditransitive (trivalent/triadic) she gave him a book tritransitive (quadrivalent/quadradic) I bet her a dollar on a horse an impersonal verb has no determinate subject, e.g. It rains. (Though it is technically the subject of the verb in English, it is only a dummy subject; that is, a syntactic placeholder: it has no concrete referent. No other subject can replace it. In some other languages, in which subjects are not syntactically obligatory, there would be no subject at all. The Spanish translation of It rains, for example, is a single verb form: Llueve.) an intransitive verb takes one argument, e.g. He1 sleeps. a transitive verb takes two, e.g. He1 kicked the ball2. a ditransitive verb takes three, e.g. He1 gave her2 a flower3. There are quadrivalent verbs that take four arguments, also called tritransitive verbs. Some schools of thought in descriptive linguistics consider bet to be tritransitive in English and as having four arguments, as in the examples I1 bet him2 five quid3 on ”The Daily Arabian”4 and I1 bet you2 two dollars3 that it will rain4. Languages that mark arguments morphologically can have indisputable "true" tritransitive verbs, which have 4 necessary arguments. In that case, these arguments may be marked by particular morphology, and may, in the case of polypersonal agreement be inflected on the verb. For example, the usage of causative morphology with a ditransitive verb in Abaza produces tritranstivity (such as the translation of the sentence "He couldn't make them give it back to her",