Symbol Grounding and the Symbolic Theft Hypothesis

Abstract

Scholars studying the origins and evolution of language are also interested in the general issue of the evolution of cognition. Language is not an isolated capability of the individual, but has intrinsic relationships with many other behavioral, cognitive, and social abilities. By understanding the mechanisms underlying the evolution of linguistic abilities, it is possible to understand the evolution of cognitive abilities. Cognitivism, one of the current approaches in psychology and cognitive science, proposes that symbol systems capture mental phenomena, and attributes cognitive validity to them. Therefore, in the same way that language is considered the prototype of cognitive abilities, a symbol system has become the prototype for studying language and cognitive systems. Symbol systems are advantageous as they are easily studied through computer simulation (a computer program is a symbol system itself), and this is why language is often studied using computational models.A symbol system is made up by a set of arbitrary "physical tokens" (i.e., symbols) that can be manipulated on the basis of explicit rules (i.e., syntax). Some of the main properties of such a symbol system are: (a) compositeness, that is symbols and rules can be recursively composed; and (b) semantic interpretability, specifying that the entire system and its parts can be systematically assigned a meaning (Pylyshyn, 1984;Harnad, 1990). Some significant issues arise when studying such symbol systems as a direct metaphor and model of language. These will also have direct implications for the study of the origins and evolution of language. The first issue is to establish exactly what a symbol is, by giving a clear

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