 Even if the role of derivational history can be avoided for scope and co-referentiality, other phenomena remain for which derivational histories have a role. An example is John wondered when Alice said she would leave. This is ambiguous between John asking for the time of leaving, or for the time of saying. So the sentence is ambiguous, even though there are no arguments for assigning to it more than one constituent structure. Pelletier (1993) presents this sentence and others, and says: ‘In order to maintain the Compositionality Principle, theorists have resorted to a number of devices which are all more or less unmotivated (except to maintain the Principle): Montagovian “quantifying-in” rules, traces, gaps, […].’ Pelletier’s objection can be appreciated if one assumes that meaning assignment is directly linked with constituent structure. But, as explained in Section  1.2,  this is not the case. The derivation specifies which rules are combined in which order, and this derivation constitutes the input to the meaning assignment function. The constituent structure is determined by the output of the syntactic rules, and different derivation processes may generate one and the same constituent structure. In this way, semantic ambiguities are accounted for. One should not call something ‘constituent structure’ if it is not intended as such, and next refute it because it does not have the desired properties.