It is possible to distinguish two different aspects of cognitive economy which work together in such a way as to restrict not only the individual parameter setting of the grammar and the lexicon, but also linguistic performance. One has as its goal the clearest possible specification of semantic primitives; the other attempts to minimize the structural complexity required for this. From the point of view of such a model, the tension between the functional and formal aspects of morphosyntactic change loses its significance, as we are able to explain both performance-based and acquisitionally-bound change within these general framework conditions. Setting purely phonotactic change aside, it can be noted that both types of change are affected by comparable inferential strategies: in both cases, changes to linguistic material are motivated by considerations of economy, albeit with performance being subject to systematic constraints, which can be overridden in the case of first language acquisition. It is for this reason that performance-based changes are usually only regularized at the stage of acquisition by the next generation. Taking as our database phenomena of change in different systems of sentence connectives, we will work here within the theoretical framework of Generative Grammar, arguing for a WYSIWYG-model.

The paper presents the results of a comprehensive case study which examined to what extent the semantics of particle verbs with auf can be understood as composed from the semantics of their parts. We give substance to our leading hypothesis that the semantics of particle constructions can be reconstructed as rule-based by means of semantics construction algorithms in a DRT-based framework. The compositional process is displayed through merging the semantic representations of the verbal root and the particle. Composition, as it is made operative in the DRT-framework, is akin to processes of presupposition justification as familiar from Dynamic Semantics. This method is shown appropriate for modelling the wide spectrum of compositional mechanisms which have to be taken into account in the formal semantics of particle verbs. The ambiguity of the particle auf can be reconstructed as restricted to only a few core meanings, some of which are familiar from the literature. We present lexical entries for the core meanings, apply them in the semantics construction and discuss sub-cases as well as metaphorical extensions.

In natural language interpretation conversational implicatures play an important role. Following Grice there are different approaches that try to approach the main ideas of Grice and to give a proper treatment of the corresponding examples and phenomena: relevance theory, neoGricean pragmatics, and Levinson's presumptive meaning approach are the most important ones. Optimality theoretic pragmatics can be seen as a general framework for formalizing the underlying notions and mechanisms. Moreover, this theory provides an excellent framework for investigating the idea of fossilization. Generally, this idea refers to the transfer from pragmatically determined information (expressed by conversational implicatures) into the formal system of language. The present paper gives a concise introduction into conversational implicatures and fossilization using the optimality-theoretic framework. The examples I discuss in this paper are mostly taken from the field of lexical pragmatics.