The Communicative Mind

为什么人类而不是猿能习得语言？根据一种标准的观点(Tomasello 2008；Scott-Phillips 2014)，只有人类才能习得语言，因为我们拥有心理理论(Tom)的生物适应能力--思考他人心理状态的能力--这是类人猿所缺乏的。这些使我们能够采取行动，并归因于‘格赖斯’(Grice 1957)的交际意图，这些意图是自然语言发展所必需的。由于类人猿缺乏汤姆，它们既不能归因于交际意图，也不能习得语言。对于标准观点来说，Gricean人交流所需的TOM似乎只有在孩子四岁左右掌握了某些自然语言形式--真实补语从句--之后才会发展起来。如果格里斯语交流所需要的思维本身是依赖于语言的，那么它就不能解释儿童的语言习得。由于新的经验数据(Krupenye&Kano，2017)也表明大猩猩的TOM类似于说话前的婴儿，标准观点没有解释大猩猩缺乏语言的原因。为了解决这些解释难题，交际性思维项目正在开发一种新的关于心理理论、语言和交流之间的关系的解释。在PI之前的工作的基础上，该项目确立了人类和类人猿之间的关键社会认知差异是文化学习的，而不是生物遗传的。该工作表明，婴儿和类人猿都可以从事社会认知方面要求不高的最低要求形式的沟通。它们的出现是因为人类，而不是猿，可以使用句法结构的话语进行交流，也因为在这种能力的支持下，几代语言使用者已经开发出语言工具，用于对精神状态进行理论推导。因此，不是汤姆解释了语言的发展，而是句法和语言的文化演变解释了汤姆的发展。孩子们通过对话和讲故事的文化实践，学习在个体发育中使用这些工具，从而获得思考思维的新工具。交际性思维项目的最初四年试图为语言在发展史中的进化和在个体发生学中语言理论的发展提供新的解释。在该项目的第二部分(4-7年，外国语2)中，我们扩展了这项工作，以考虑人类其他独特的认知形式--包括在过去和未来思考我们自己的能力(心理时间旅行)以及其他认知特征--在发展上也依赖于自然语言的文化进化。这些项目将结合在一起，讲述使用语言的能力的起源，以及语言改变人类认知的方式。通过展示人类独特的认知特征通过交流产生，我们将展示人类思维的根本社会基础。随后，我们将利用我们的发现开发支持儿童学习的教育工具，并重新考虑现有动物福利标准的适当性，基于对动物和人类之间认知连续性的新认识。

Why do humans but not apes acquire language? According to a standard view (Tomasello 2008; Scott-Phillips 2014) humans alone acquire language because we possess biological adaptations for Theory of Mind ('ToM') - the ability to think about others' mental states - that great apes lack. These enable us to act with and attribute the 'Gricean' (Grice 1957) communicative intentions that are necessary for natural language development. Since great apes lack ToM, they can neither attribute communicative intentions nor acquire language. Problematically for the standard view, the ToM needed for Gricean communication seem to develop only with the mastery of certain natural language forms - 'realis complement clause' syntax - around children's fourth birthday. If the mindreading needed for Gricean communication is itself language dependent, then it cannot contribute to an explanation of children's language acquisition. Since new empirical data (Krupenye & Kano, 2017) also shows that the ToM of great apes is similar to that of pre-verbal infants, the standard view leaves the absence of language in great apes unexplained. To dissolve these explanatory puzzles, the Communicative Mind project (FLF1) is developing a new account of the relationship between ToM, language, and communication. Building on the PI's previous work, which shows that infants and apes alike can engage in socio-cognitively undemanding forms of 'minimally Gricean' communication, the project establishes that key socio-cognitive differences between humans and apes are culturally learned, not biologically inherited. They emerge because humans but not apes can use syntactically structured utterances to communicate, and because on the back of this ability generations of language-users have developed linguistic tools for theorising about mental states. Thus, it is not ToM that explains the development of language, but syntax and the cultural evolution of language that explains the development of ToM. Children learn to use these tools in ontogeny, through cultural practices of conversation and storytelling, and thereby acquire new tools for thinking about minds. The initial four years of the Communicative Mind project (FLF1) has sought to develop new accounts of the evolution of language in phylogeny, and of the development of ToM in ontogeny. In the second part of the project (years 4-7, FLF2), we extend this work to consider the extent to which other uniquely human forms of cognition - including the ability to think of ourselves in the past and future ('mental time travel'), among other cognitive traits - are also developmentally dependent upon the cultural evolution of natural languages. These projects will combine to give an account of the origins of the ability to use language, and of the ways in which language has changed human cognition. By showing that uniquely human cognitive traits emerge through communication, we will demonstrate the fundamentally social foundations of human thought. Subsequently we will use our findings to develop educational tools to support children's learning, and to reconsider the appropriateness of existing standards of animal welfare, grounded in a new appreciation of the cognitive continuity between animals and humans.