MORPHOLOGY: a principle proposed in Williams (1981a) to account for
bracketing paradoxes, which says that X can be related to Y if X and Y differ only in a head position or in the
non-head position. Williams views the question of bracketing paradoxes from the perspective of a concept of relatedness between lexical entries. In his terms, the problem is to explain how words such as hydroelectric and
hydroelec-tricity are related to each other, and to the words electric and electricity. From a morphological point of view one has to assign the following structure to hydroelectricity:
[hydro [electric+ity]]. However, the semantically motivated structure for this word is [[hydro+electric] ity]. Williams' solution runs as follows. He assigns the structure [hydro [electric+ity]] to this word, and due to the principle of Lexical Relatedness he can relate hydroelectricity
(= X) to hydroelectric (= Y), since they differ only in the head position (= -ity).