(A)symmetries and movement in spoken and sign languages

句子组织中最有趣的特性之一是某些类型的“左右不对称”（LRA）的普遍性。一个得到充分证明的不对称关系到初始指定顺序优于最终指定顺序。这种不对称提出了一个问题，即底层结构本身在多大程度上是不对称的。在过去的几十年里，除了潜在句法结构的对称性之外，研究至少产生了两种相反的观点。在一种方法中，语法是基本对称的，因为它可以输出指定符-最终或指定符-初始顺序，以及头-初始或头-最终顺序。在这种“对称”的方法中，说明词的初始顺序比说明词的最终顺序的优势可能来自“禁止向右移动”（BORM），这甚至可能来自语法之外的原则。在另一种“不对称”的方法中，所有的短语都按照指定者-头部-补语（SHC）的顺序线性化，而偏离SHC模式的模式必须通过一系列的移动来派生。这两种方法都面临着经验上的障碍，语法到底是对称的还是不对称的这个基本问题仍然没有答案。为了解决这个问题，本项目关注两个感兴趣的领域：(i)口语中现有的LRA（以及这些LRA是否遵循BORM或其他内容）和（ii）手语中现有的LRA，以及它们与口语的区别。总体目标是确定(i)和（ii）中研究的现象在多大程度上为语法外部BORM作为句法LRA的唯一来源提供证据，以及语法外部因素（如情态）在多大程度上导致表面不对称。LRA通常被用作支持非对称方法的论据。第一步是调查口语和手语的核心语法是否一定是不对称的。如果现有的LRA也可以说是由于被认为是语法外的BORM，那么它们可以完全兼容对称和非对称的语法观点。这样的上帝抵抗军可能不再提供支持不对称方法的证据。事实上，如果所有现有的LRA都可约化为BORM，那么就没有实证论证可以追求不对称方法了。第二步是调查向左移动的丰富和向右移动的稀缺是否直接反映了主要的不对称语法，或者这种不对称是否由于任何独立的、语法之外的原因而出现，例如解析限制和情态的影响。由于向右移动在手语中更为普遍，我们的目标是更多地阐明为什么手语缺乏口语所受的约束，以及手语中缺乏这种约束告诉我们的是(a)底层结构的对称性。

One of the most intriguing properties of organization of sentences is the pervasiveness of certain kinds of “left-right asymmetries” (LRA). A well-attested asymmetry concerns the preponderance of specifier-initial orders over the specifier-final orders. This asymmetry raises the question to what extent the underlying structure itself is asymmetric. Over the last few decades the inquiry yielded (at least) two opposing views w.r.t. the symmetry of the underlying syntactic structure. In one approach, grammar is underlyingly symmetric in that it can output either specifier-final or specifier-initial orders, as well as either head-initial or head-final orders. In this “symmetric” approach, the preponderance of specifier-initial over specifier-final orders may follow from a “ban on rightward movement” (BORM), which may even follow from extra-grammatical principles. In the other “asymmetric” approach, all phrases are linearized in the specifier-head-complement (SHC) orders while patterns that deviate from the SHC schema must be derived via a series of movements. Both approaches continue to face empirical hurdles and the fundamental question of whether grammar is underlyingly symmetric or asymmetric remains unanswered. With the aim of addressing this question, this project focuses on two areas of interest: (i) existing LRA in spoken languages (and whether these follow from the BORM or something else) and (ii) existing LRA in sign languages, and how they differ from spoken languages. The overarching goal is to determine the extent to which the phenomena studied in (i) and (ii) provide evidence for a grammar-external BORM as the sole source for syntactic LRA, as well as the extent to which grammar-external factors, such as modality, contribute to surface asymmetries.LRA have generally been used as arguments in favor of the asymmetric approach. The first step is to investigate in both spoken and sign languages whether grammar at its core must be asymmetric. If existing LRA can also be said to be due to the BORM that is conceived of as extra-grammatical, they can be fully compatible with both a symmetric and an asymmetric perspective on grammar. Such LRA, may then no longer provide evidence in favor of asymmetric approach. In fact, if all existing LRA are reducible to the BORM, there would be no empirical argument left to pursue the asymmetric approach.The second step is to investigate whether the abundance of leftward and the scarcity of rightward movement directly reflect a principally asymmetric grammar, or whether this asymmetry emerges for any independent, extra-grammatical reasons, such as the parsing limitations and the effects of modality. Since rightward movement is more pervasive in sign languages, our goal is to shed more light on why sign languages lack the constraints that spoken languages are subject to and what does the absence of such constraints in sign languages tell us about the (a)symmetry of the underlying structure.