Projection principle
The projection principle and the Extended Projection Principle (EPP) are linguistic principles within the generative transformational grammar , which in theory framework of the Government and Binding of Noam Chomsky were committed.
The older projection principle, as well as the more current extended projection principle are:
- Lexical information is represented syntactically .
- All sentences need a subject .
The following sentences are examples of the principles:
- a) It is likely that Hans is sleeping.
- b) * Hans is likely to sleep.
First to the verb argument structure in the matrix sentence : X is likely to require an embedded complementary sentence , as well as a subject, because of the grammaticality of the following sentences: * It is likely that Hans is asleep. and * it is likely. The extended projection principle does not explain why sentences need a subject, but was introduced out of necessity.
The theta theory states that each theta role must be assigned exactly once. b) suggests that this does not seem to work in the case of Hans , i.e. that the verb only has a theta role to assign. The projection principle states that a verb unfolds its lexical information in such a way that it becomes visible in the syntax. The argument structure is coded in the so-called theta grid . For example, the German verb snore requires an argument, namely a subject as in Hans snores . * Hans snores the cake , however, is impossible. So snoring is a one-digit verb. To step is a two-digit verb, give a three-digit etc. If the number of arguments required is not met, the principle is violated and the sentence is ungrammatic.
There in a) is a syntactic expletive : syntactically it falls under the category of determiners phrase (DP) and contributes nothing to the semantic meaning of the sentence in (cf .: The fact that Hans sleeps is likely. And not: * The fact that Hans is sleeping, it is probably. ). Furthermore, after the expletive it is not possible to ask meaningfully: * What is likely that Hans is sleeping? (Answer: it ), but: what is likely? (Answer: that Hans is sleeping ).
The extended projection principle also requires that every sentence must have a subject. This explains the need for an expletive. In pro-drop languages (e.g. Italian , Latin ) this looks different: Here the subject is not represented syntactically, but is sometimes only visible in the inflection of the verb.
literature
- Poole, G. 2002. Syntactic Theory . Houndmills: Palgrave.