Movement paradox

A movement paradox is a phenomenon of grammar that challenges the transformational approach to syntax. The importance of movement paradoxes is emphasized by those theories of syntax (e.g. lexical functional grammar, head-driven phrase structure grammar, construction grammar, most dependency grammars) that reject movement, i.e. the notion that discontinuities in syntax are explained by the movement of constituents.

Given a transformational approach to syntax, the following related sentences are explained in terms of movement:

The underlined noun phrase, which contains a clause, is taken to have moved leftward in the second sentence, the blank marking its starting position. A transformational approach to syntax will explain all sorts of discontinuities (e.g. wh-fronting, topicalization, extraposition, scrambling, inversion, shifting) in this manner in terms of movement.

Movement paradoxes challenge the movement account of discontinuities. They occur when the "moved" constituent is acceptable in its derived position but not in its base position, e.g.

These data are difficult to explain in an analysis based on movement, since it is not evident how the b-sentence can be grammatical each time if it is derived by a movement operation applied to the corresponding a-example. The first example illustrates a movement paradox involving a clausal complement of the preposition about, the second a movement paradox involving competing forms of a non-finite verb (meet vs met), and the third a movement paradox involving a contracted form of the copula (aren't). To state the problem in other words, the movement analysis of the b-sentences has to explain the unexpected fact that the a-sentences are bad.

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