Experiments on the Acquisition of the Semantics and Grammatical Constructions Required for Communicating Propositional Logic Sentences

We describe some experiments which simulate a grounded approach to language acquisition in which a population of autonomous agents without prior linguistic knowledge tries to construct at the same time a conceptualisation of its environment and a shared language. The conceptualisation and language acquisition processes in each individual agent are based on general purpose cognitive capacities, such as categorisation, discrimination, evaluation and induction. The emergence of a shared language in the population results from a process of selforganisation of a particular type of linguistic interaction which takes place among the agents in the population. The experiments, which extend previous work by addressing the problem of the acquisition of both the semantics and the syntax of propositional logic, show that at the end of the simulation runs the agents build different conceptualisations and different grammars. However, these conceptualisations and grammars are compatible enough to guarantee the unambiguous communication of propositional logic sentences. Furthermore the categorisers of the perceptually grounded and logical categories built during the conceptualisation and language acquisition processes can be used for some forms of common sense reasoning, such as determining whether a sentence is a tautology, a contradiction, a common sense axiom or a merely satisfiable formula.