Interspecies communication, consciousness, and the cognitive verb gap* John Limber Department of Psychology University of New Hampshire, Durham NH 03824 KEYWORDS: interspecies communication, language acquisition, cognitive verbs, metacognition, language evolution * Abstract of paper presented at "Toward a Science of Consciousness", University of Arizona, April 8-13, 1996. _______________________ There is a long history to human-animal communication in a "human-language based" (HLB) code. This is reflected in the practical knowledge accumulated over thousands of years experience with domestic animals and in recent scientific investigations (2). Underlying this idea of a HLB code is that various species share certain concepts --most obviously of actions and objects--that can be the topics of interspecies communication. While the direction of communication generally goes from human to other species, the flow can go the other way. When my dog wants something in my control -- food, a bone, water, or to go out-- she makes her needs known using standard "mammalese." Establish eye contact, whimper with laryngeal squeaks, touch me if necessary to get my attention. Now that my attention is engaged, she expects me to articulate the limited possibilities and she will jump at the correct one. Some organisms-- notably large apes but even birds-- when properly equipped or trained, can acquire control of specific HLB symbols that make their initiation of communication even more effective. For much of HLB communication --like that with my dog-- little explicit training seems necessary; with varying amounts of interaction, they seem able to associate their mental states with the HLB code. This paper looks at interspecies communication with the objective of illuminating our own species' use of language. As with other biological processes like locomotion, there is a common substrate to cognition and communication across related species. There are qualitative and quantitative gaps as well. THE COGNITIVE VERB GAP Some years ago, in connection with reports about the "minds" of chimpanzees, I noted (Limber, 1977; 1978) the existence of a "Cognitive verb gap." While all children begin to use cognitive verbs like "think" simultaneously with the appearance of syntactic language in their third year (Limber, 1973), no one claims that any chimps discourse on their own thoughts. Suppose we fully accept at face value both the claims about chimpanzees using human language, and the research suggesting varying degrees of mind and consciousness in those same primates. We then --by hypothesis-- confront organisms that are thinking, conscious beings who do not talk about those processes or states of mind. Conceivably an intermediate stage of mind-evolution, it is a curious situation since a common interpretation of these ape-language studies is that the HLB expressions map onto existing cognitive states. Indeed, many believe this is true in the case of Homo sapiens as well. Yet if this is true-- and these animals actually do think, guess, and wonder--why don't they inform us about it in the same way they can signal us they want bones, tickles, or to go out? What does this tell us about mind and language in child and chimp? Several possibilities are considered in the course of tracing the ontogeny of the English verb "think" during the first four years: human cognition is qualitatively different from animals and/or human language acquisition is not a simple labeling of mental states. FOOTNOTE 2 See references. REFERENCES Gladden, G. (1914). A chimpanzee's vocabulary. Outlook, 106, 307- 310. Lubbock, J. (1884). Teaching animals to converse. Nature, 2, 547-548. Limber, J. (1973). 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