Language Acquisition

Language acquisition is one of the central topics in cognitive science. Every theory of cognition has tried to explain it; probably no other topic has aroused such controversy. Possessing a language is the quintessentially human trait: all normal humans speak, no nonhuman animal does. Language is the main vehicle by which we know about other people's thoughts, and the two must be intimately related. Every time we speak we are revealing something about language, so the facts of language structure are easy to come by; these data hint at a system of extraordinary complexity. Nonetheless, learning a first language is something every child does successfully, in a matter of a few years and without the need for formal lessons.
A related question is whether language is unique to humans. At first glance the answer seems obvious. Other animals communicate with a fixed repertoire of symbols, or with analogue variation like the mercury in a thermometer. But none appears to have the combinatorial rule system of human language, in which symbols are permuted into an unlimited set of combinations, each with a determinate meaning. On the other hand, many other claims about human uniqueness, such as that humans were the only animals to use tools or to fabricate them, have turned out to be false. Some researchers have thought that apes have the capacity for language but never profited from a humanlike cultural milieu in which language was taught, and they have thus tried to teach apes language-like systems.

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参考译文
语言习得
语言习得是认知科学中的中心话题。每一种认知理论都试图解释它。可能没有其他的话题能引起这样的争论。掌握语言是人类的典型特征；所有正常人都可以讲话，而非人类的动物则不能。语言是我们了解其他人思想的主要手段（工具），两者一定是密切相关。每次我们讲话都在显现一些关于语言的东西，因此语言结构的事实就很容易获得了，这些资料暗示着一个异常复杂的系统。然而，学会第一语言是每个孩子都成功作到的事情，只要用几年的时间，并不需要正规的课程。

一个相关的问题是：语言是否是人类独有的。初看，答案似乎是明显的。其他的动物用固定的、符号系统交流，或用一种象温度计里的水银那样的模拟变化方式交流。但看来他们都没有人类语言这样组合的规则体系，在这系统里符号排列变化成一套无限的组合，　每一种都有确定的含义。另一方面，许多有关人类特有性的断言后来证明是错误的，如人类是唯一使用或者制造工具的动物。有些研究者们认为猿有语言能力但从来没有得益于象人类那样的实行语言教学的文化环境，因此他们试图教猿类似语言的体系。