Grammatical agreement means that two linguistic units share certain syntactic or semantic features such as gender, number or person. Agreement has a variety of grammatical functions. One of them, called internal agreement, is to signal which words are grouped together as part of the same phrase. This chapter explores how a population might self-organize such an agreement system. We argue that this happens when speakers attempt to reduce processing effort and avoid ambiguities. 1.

This chapter explores a semantics-oriented approach to the origins of syntactic structure. It reports on preliminary experiments whereby speakers introduce hierarchical constructions and grammatical markers to express which conceptualization strategy hearers are supposed to invoke. This grammatical information helps hearers to avoid semantic ambiguity or errors in interpretation. A simulation study is performed for spatial grammar using robotic agents that play language games about objects in their shared world. The chapter uses a reconstruction of a fragment of German spatial language to identify the niche of spatial grammar, and then reports on acquisition and formation experiments in which agents seeded with a ‘pidgin German ’ without grammar are made to interact until rudiments of hierarchical structure and grammatical marking emerge. 1.

This chapter outlines the main challenges a theory for the cultural evolution of language should address and proposes a particular theory which is worked out and explored in greater detail in the remaining chapters of this book. The theory rests on two biologically inspired mechanisms, namely selection and self-organization, mapped onto the cultural, more specifically, linguistic domain. Selectionism is an alternative to rational top-down design. It introduces a distinction between processes that generate possible linguistic variants in a population (for example, different ways to express tense and aspect) and processes that select some variants to survive and become dominant in a language, based on criteria that translate into increased communicative success, such as expressive adequacy, minimal cognitive effort, learnability and social conformity. Self-organization occurs when speakers and hearers align their communication systems based on the outcome of each interaction. It explains how convergence may arise without central coordination or direct telepathic meaning transfer. This chapter explains these basic hypotheses in more detail and introduces a methodology for exploring them based on the notion of a language game. 1.

Abstract. Becoming a proficient speaker of a language requires more than just learning a set of words and grammar rules, it also implies mastering the ways in which speakers of that language typically innovate: stretching the meaning of words, introducing new grammatical constructions, introducing a new category, and so on. This paper demonstrates that such meta-knowledge can be represented and applied by reusing similar representations and processing techniques as needed for routine linguistic processing, which makes it possible that language processing makes use of computational reflection. 1