Review of The Equilibrium of Human Syntax
This book is a collection of work conducted by Andrea Moro in two different, though intersecting, fields of generative syntax and neurolinguistics. It starts with the author’s retrospective introduction of his work collected here. The book consists of two parts. Part I (“Symmetry (Breaking) in Syntax”) reproduces his papers on copular constructions, existential sentences and, among others, on his influential theory of Dynamic Antisymmetry (DA). Part II (“The Boundaries of Babel: How the Brain Shapes Grammars”) includes papers reporting results of various neuroimaging experiments bearing on important issues such as selective anomalies, brain sensitivity to recursive vs. non-recursive rules, and the neuropsychological effects of sentential negation in the brain.
Part I consists of two sections -- “Inversion and Clause Structure” and “Clause Structure Folding and Other Left Peripheral Issues”. Section 1, in turn, has two sub-sections – “Copular Syntax” and “Symmetry, Movement and Locality in Syntax”. In the first chapter of section 1.1, Moro proposes a unified analysis of canonical and inverse copular sentences. Examples (1a, b) illustrate the two types of sentences:
(1)a. [A picture of the wall] is [the cause of the riot]. (Canonical copular sentence)
b. [The cause of the riot] is [a picture of the wall]. (Inverse copular sentence)
Moro proposes that the subject and predicative NPs occupy the specifier and complement of the independent Agr head, respectively. The two types of sentences are derived by raising either the first NP or the second NP to [Spec, T]. The second chapter explores consequences of this analysis for locality. An inverse copular clause blocks extraction both from the postverbal NP and of the NP itself. This is explained by a locality theory which encompasses both Subjacency and the Empty Category Principle (ECP). This hybrid theory is supported by the fact that in Italian existential constructions, extraction from the postverbal NP is fine but extraction of the NP is not. The third chapter discusses further anomalies of inverse copular sentences in Italian and demonstrates how the unified theory can accommodate them. The fourth chapter proposes a new analysis of “there”-existential constructions as a subtype of inverse copular sentences: “there” is the raised placeholder for the predicate, not for the subject of the predication, as assumed since Milsark (1974) and Chomsky (1981). This alternative analysis provides a simple explanation for otherwise mysterious properties of existential constructions in English and Italian concerning extraction, cliticization, and secondary predicates. The fifth chapter outlines a history of analyses of the copula, reviewing the definitions of the term proposed by Aristotle, Abelard, Russel, Jespersen and Chomsky.
The first chapter of section 1.2 suggests a new uniform characterization of the notion of proper governors central to the ECP. Chomsky (1986) attempted to reduce the ECP to antecedent government whereas Rizzi (1990) attempted to reduce it to head government. Moro proposes that a rather straightforward characterization of proper governor becomes readily available once we consider the role of agreement. The second chapter proposes movement as a symmetry-breaking phenomenon. Within the standard minimalist framework (Chomsky 1995), movement occurs for morphological reasons. Moro shows that this theory cannot account for the fact that the subject of an inverse copular sentence cannot be moved. Consider the inverse copular sentence in (2) (where SC stands for Small Clause): both DPs in (2) should be able to move to the specifier of the relevant functional heads to check their formal features such as Case features.
(2) * [Which pictures]i do you think [the cause of the riot]j is [SC ti tj]? (p. 153)
Adopting a weaker version of Kayne’s (1994) Linear Correspondence Axiom, Moro proposes an alternative theory of DA, which states “…Universal grammar allows the generation of points of symmetry, provided that the set of terminal nodes dominated by either non-terminal node constituting this point of symmetry be moved” (p. 155). This theory correctly predicts that in SC configurations like (3a), one of the NPs can and must be raised to the pre-copular position.
(3)a. [SC [these pictures] [the cause of the riot]]
b. [these pictures] are [SC t [the cause of the riot]]
c. [the cause of the riot] is [SC [these pictures] t]] (p. 158)
The third chapter situates DA along the lines of the suggestion made by Chomsky (2001) that central syntactic properties may be explained in terms of conditions imposed on the language faculty by physical laws. Moro argues that movement occurs “as a consequence of the physical necessity to organize words into a linear order” (p. 179) or linear compression. One major consequence of this theory is that natural language should exhibit “mirror structures”, where two elements X and Y constitute a point of symmetry and can occur in either order. He shows that this prediction is indeed borne out across a wide range of cases encompassing IP, AP and DP domains. The last chapter considers why pro-insertion cannot save SC configurations of the form [pro copula [SC XP YP]] and suggests that this configuration is ill-formed because the label of the SC is underdetermined, rendering the search domain for any head ambiguous.
The first chapter of section 2 argues that the apparent wh-in-situ effect in Italian arises from the process of “clause structure folding” (p. 210). This process is illustrated in (4d).
(4)a. … [TP wh-phrase1 … wh-phrase2]
b. … [wh-phrase2 C [wh-phrase1 C [TP … t1 … t2]]]
c. … [ [(e)] [wh-phrase2 C [wh-phrase1 C [TP … t1 … t2 …]]]]
d. … [[wh-phrase1 C [TP … t1 … t2]]j [[(e)] [wh-phrase2 C tj]]]] (p. 224)
Both wh-phrases move to [Spec, C]. After the coordinator “e” is introduced, the lower portion of the CP is moved to [Spec, e] moving across the wh-phrase2. This analysis provides a principled account for various facts including coordination, free relatives, and selective interpretations of negation.
The second chapter introduces diagnostics for vocative phrases in Italian and suggests a new analysis of such phrases within Rizzi’s (1997) cartographic theory.
Part II consists of three sections: “Syntax in the Brain,” “Impossible Languages,” and “How Much World is There in the Language?”. The first chapter of section 1 reports on the results of an experiment to answer the intriguing question whether the syntactic module has a dedicated neurophysiological correlate. The experiment ingeniously designed language stimuli (pseudo-Italian) where all lexical roots are substituted by invented roots while keeping functional morphemes preserved to isolate dedicated correlates of morphosyntactic and syntactic processing (agreement errors and word order errors, respectively). The experiment tested the brain activations of the subjects who were asked to covertly read sentences presented visually and make acceptability judgments at three levels: syntactic, morphosyntactic and phonotactic levels. The results of this experiment are encouraging in suggesting that “it is a specific portion of Broca’s area (i.e., Ba 45) within the depth of the lateral sulcus in the inferior frontal gyrus, to be activated by both the morphosyntactic and the syntactic task” (p. 257). The second chapter explores neural substrates of language switch by bilingual speakers during sentence comprehension. The stimuli used in this experiment were of two types: regular switches which respect the constituency of sentence structures vs. irregular switches which violate the constituency. The experiment investigated the imaging results of Italian/French bilinguals. The results of the experiment show that “the activation of regions related to lexical processing, such as the left Ba 37, was specific for regular switches, whereas irregular switches resulted in the activation of the opercular portion of Broca’s area and the LIPL.” (p. 273).
The first chapter of section 2 investigates activation loci of adults’ brains through the fMRI when they acquire UG-compliant rules (G rules) vis-à-vis UG-non-compliant rules (NG rules). In the experiment reported here, Italian-speaking subjects silently read sentences which include either G- or NG-rules: the former are based on hierarchical relations whereas the latter are based on the absolute position of some elements within the linear sequence of words. The results of the experiment show that “G rules activated the opercular portion of Broca’s area (Ba 44), the left dorsal premotor area (Ba 6), and the left angular gyrus (Ba 39)” whereas “NG rules activated the right middle frontal gyrus (Ba 46) and the right superior parietal lobule (Ba7).” (p. 291). This result argues for selective participation of Broca’s area in the acquisition of hierarchical grammatical rules of syntax as opposed to linear-based rules.
The second chapter reports on an experiment which exposed German speakers to grammatical/hierarchy-based rules of Italian/Japanese and artificial ungrammatical/linear-based rules of the unreal languages based on selective manipulations of the two languages to measure their brain reactions to judgments of the two types of rules by means of fMRI techniques. The results of this experiment are taken to suggest that Broca’s area is specialized for processing hierarchical structures rather than linear structures. It is also reported that subjects’ reaction times became progressively faster during the real grammatical tasks than during the unreal grammatical tasks.
The final chapter corroborates the major conclusion reached in the previous chapter by using non-linguistic symbols under two conditions: in non-rigid syntactic dependencies (NRSDs), two symbols agree in color and size and their position varies freely whereas in right syntactic dependencies (RSDs), two symbols not only agree in color and size but also occur in an absolute fixed order. The fMRI data analysis showed that “the bilateral fronto-parietal network engaged by the acquisition of symbol-based syntax was largely equivalent to the network engaged by the acquisition of word-based syntax” (p. 335). This result indicates that NRSD is not specific to particular cognitive domains such as language.
The first chapter of section 3 studies the modulatory effects of sentential negation on the neural systems activated by action-related vs. abstract propositions. In the fMRI experiment reported here, participants were asked to listen to sentences characterized by a factorial combination of polarity (affirmation vs. negation) and concreteness (action-related vs. abstract). It is shown on the basis of functional integration analyses that the modularity effects for action-related as opposed to abstract sentences were stronger in affirmative than in negative sentences. This result is taken to support the view that activation spread into conceptual systems is reduced in the case of sentential negation.
The second chapter critically reviews the so-called Mirror Neuron System (MNS) theory of language as applied to phonetics, semantics and syntax. It is stated that such a theory is quite limited in scope despite the fact that some aspects of phonetic and semantic processing seem amenable to perceptuo-motor functions. The main argument of this chapter is that an MNS theory is particularly unsuitable for syntax because syntactic structures are two-dimensional complex objects, rendering them inaccessible to any direct sensory perception. This does not mean, however, that the internal computational capacities for syntax may never interact with the perceptuo-motor system. The results from the experiment reported in the previous chapter are mentioned here as one case where the two systems can interact. The third chapter suggests that human language could be viewed as “kataptation”, namely, “the persistence in a population of a trait that survives unmodified even if the original function that the trait was selected for disappeared and no other function has replaced it” (p. 390), just on a par with the QWERTY layout which currently prevails in our electronic computers despite its synchronically unexplainable function.
The last chapter contains a critical review of the quantitative neuropsychological data from Pallier et al. (2011) suggesting that words are combined into hierarchical structures rather than linearly ordered. The chapter discusses various issues raised by this research, including compatibility of their results with independent discoveries in the field, the kinds of experiments to be expected in the future and the possible reduction of central syntactic features to extra-linguistic capacities.
Part I provides the reader with the unique opportunity to chronologically track the development of syntactic research and thinking by Moro in the last 25 years. Moro mentions that “... theories ... do not ... come from envisaging a new world system as a whole but as the catastrophic effect of solutions to specific problems” (p. 3). The papers collected in Part I are impeccable testimony to this statement; the unified transformational analysis of canonical and inverse copular sentences developed in his undergraduate honor thesis, whose synthesis is collected in the first chapter of section 1.1, allows him to draw far-reaching empirical and theoretical consequences for many other areas of syntactic theorizing (e.g., the predicate-theory of expletives, the agreement-based approach to the notion of proper governors, dynamic antisymmetry, symmetry-breaking, linear compression and the underdetermined theory of labeling). Nobody knows whether his/her solution to a particular empirical problem will turn out to yield a new deep understanding of syntax later in his/her lifetime but every reader should be amazed by Moro’s gifted ability to originate theoretical advances in syntax through the apparently simple analysis of a simple paradigm he proposed some 25 years ago.
The chapters in Part II include many details regarding experimental stimuli and data analyses which go beyond the limited capacity of theoretical syntacticians (myself included), but the rationale behind, and the design of, each experiment reported here is laid out very clearly. The various neuroimaging experiments are all unique attempts to identify exclusive neurophysiological correlates of foundational postulates hypothesized by the generative enterprise (e.g., constituent structure, hierarchy vs. linear order, NRSDs vs. RSDs) and to test the contrasting predictions of various approaches (e.g., MNS theories) to language acquisition and evolution. The chapters also show that neurolinguistic experiments like the ones reported here are only possible when backed up by solid understandings of core architectural design features of human language syntax.
For syntacticians, this volume should allow them an exciting glimpse into the development of Moro’s own thinking on various issues in generative theory from 1988 to the present. For neurolinguists, the volume should inform them what kinds of neuroimaging experiments are to be expected in the future based on the current state of the art in syntactic research. Either way, there is no denying that this book represents a unique and fruitful integration of theoretical syntax and neurolinguistics by one of the most brilliant contemporary minds.
Milsark, G. 1974. Existential sentences in English. Doctoral dissertation, MIT.
Chomsky, N. 1981. Lectures on government and binding. Dordrecht: Foris.
Chomsky, N. 1986. Barriers. Cambridge, MA: MIT Press.
Chomsky, N. 1995. The minimalist program. Cambridge, MA: MIT Press.
Chomsky, N. 2001. Beyond explanatory adequacy. MITWPL 20. Department of Linguistics and Philosophy: MIT.
Kayne, R. 1994. The antisymmetry of syntax. Cambridge, MA: MIT Press.
Pallier, C., Devauchelle, A.D., & Dehaene, S. 2011. Cortical representation of the constituent structure of sentences. Proceedings of the National Academy of sciences USA 108: 2522-2527.
Rizzi, L. 1990. Relativized minimality. Cambridge, MA: MIT Press.
Rizzi, L. 1997. The fine structure of the left periphery. In Liliane Haegeman (ed.), Elements of grammar, Dordrecht: Kluwer.
| ABOUT THE REVIEWER:
Yosuke Sato received his PhD in linguistics in 2008 from the University of Arizona, Tucson. He is currently Assistant Professor at the Department of English Language and Literature at the National University of Singapore. He works on syntactic theory and linguistics interfaces from the perspective of Asian languages (esp. Indonesian, Javanese, Malay, Japanese) and World Englishes (Singapore English). He has published his research in journals such as Linguistic Inquiry, Journal of East Asian Linguistics, Journal of Linguistics, Syntax, and Studia Linguistica. His current interests revolve around syntactic mechanisms of contact-induced changes and the evolution of the human language faculty.