Statistical Physics of Language Evolution: The Grammaticalization Phenomenon Quentin Feltgen To cite this version: Quentin Feltgen. Statistical Physics of Language Evolution: The Grammaticalization Phenomenon. Physics [physics]. PSL research University, 2017. English. tel-01753835v1 HAL Id: tel-01753835 https://tel.archives-ouvertes.fr/tel-01753835v1 Submitted on 29 Mar 2018 (v1), last revised 7 Jun 2018 (v2) HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THÈSE DE DOCTORAT de l’Université de recherche Paris Sciences et Lettres PSL Research University Préparée à l’École Normale Supérieure Statistical Physics of Language Evolution: The Grammaticalization Phenomenon Physique statistique de l’évolution des langues : le cas de la grammaticalisation Ecole doctorale n°564 PHYSIQUE EN ÎLE-DE-FRANCE Spécialité PHYSIQUE DE LA COMPLEXITÉ COMPOSITION DU JURY : Mme HERNÁNDEZ Laura LPTM, UCP, Présidente du jury M. BLYTHE Richard University of Edinburgh, Rapporteur Soutenue par M. HILPERT Martin Université de Neuchâtel, Rapporteur Quentin FELTGEN le 11 octobre 2017 Mme PRÉVOST Sophie h LaTTiCe, ENS, Examinateur M. TAILLEUR Julien Dirigée par Jean-Pierre Nadal MSC, Université Paris Diderot, Co-encadrée par Benjamin Fagard Examinateur M. NADAL Jean-Pierre h LPS, ENS & CAMS, EHESS, Directeur de thèse M. FAGARD Benjamin LaTTiCe, ENS, Co-encadrant Logo de votre établissment Logo de l’établissement partenaire Résumé Cette thèse se propose d’étudier la grammaticalisation, processus d’évolution linguis- tique par lequel les éléments fonctionnels de la langue se trouvent remplacés au cours du temps par des mots ou des constructions de contenu, c’est-à-dire servant à désigner des entités plus concrètes. La grammaticalisation est donc un cas particulier de rem- placement sémantique. Or, la langue faisant l’objet d’un consensus social bien établi, il semble que le changement sémantique s’effectue à contre-courant de la bonne effi- cacité de la communication ; pourtant, il est attesté dans toutes les langues, toutes les époques et, comme le montre la grammaticalisation, toutes les catégories linguis- tiques. Dans cette thèse, nous étudions d’abord le phénomène de grammaticalisation d’un point de vue empirique, en analysant les fréquences d’usage de plusieurs cen- taines de constructions du langage connaissant une ou plusieurs grammaticalisations au cours de l’histoire de la langue française. Ces profils de fréquence sont extraits de la base de données de Frantext, qui permet de couvrir une période de sept siècles. L’augmentation de fréquence en courbe en S concomitante du remplacement séman- tique, attestée dans la littérature, est confirmée, mais aussi complétée par l’observation d’une période de latence, une stagnation de la fréquence d’usage de la construction alors même que celle-ci manifeste déjà son nouveau sens. Les distributions statistiques des observables décrivant ces deux phénomènes sont obtenues et quantifiées. Un modèle de marche aléatoire est ensuite proposé reproduisant ces deux phénomènes. La latence s’y trouve expliquée comme un phénomène critique, au voisinage d’une bifurcation point-col. Une extension de ce modèle articulant l’organisation du réseau sémantique et les formes possibles de l’évolution est ensuite discutée. i ii RÉSUMÉ Abstract This work aims to study grammaticalization, the process by which the functional items of a language come to be replaced with time by content words or constructions, usually providing a more substantial meaning. Grammaticalization is therefore a particular type of semantic replacement. However, language emerges as a social consensus, so that it would seem that semantic change is at odds with the proper working of commu- nication. Despite of this, the phenomenon is attested in all languages, at all times, and pervades all linguistic categories, as the very existence of grammaticalization shows. Why it would be so is somehow puzzling. In this thesis, we shall argue that the com- ponents on which lies the efficiency of linguistic communication are precisely those responsible for these semantic changes. To investigate this matter, we provide an empirical study of frequency profiles of a few hundreds of linguistic constructions un- dergoing one or several grammaticalizations throughout the French language history. These frequencies of use are extracted from the textual database Frantext, which covers a period of seven centuries. The S-shaped frequency rise co-occurring with semantic change, well attested in the existing literature, is confirmed. We moreover complement it by a latency part during which the frequency does not rise yet, though the construc- tion is already used with its new meaning. The statistical distribution of the different observables related to these two phenomenal features are extracted. A random walk model is then proposed to account for this two-sided frequency pattern. The latency period appears as a critical phenomenon in the vicinity of a saddle-node bifurcation, and quantitatively matches its empirical counter-part. Finally, an extension of the model is sketched, in which the relationship between the structure of the semantic network and the outcome of the evolution could be discussed. iii iv ABSTRACT Acknowledgements When I came up four years ago with the obsessive idea to work on language, I went to a ‘find your thesis supervisor’ event organized by the ENS and met Jean-Pierre Nadal. He was talking about his work on categories and neural networks, and at some point I interrupted him and said: “I would like very much to work on language. Would you agree to supervise a PhD on this topic?” He not only agreed, he also asked for two lin- guists to come, Benjamin Fagard and Thierry Poibeau, whom he knew were interested in empirical approaches on language. Fortunately, despite the vagueness of my wish, what Benjamin Fagard and Thierry Poibeau had in mind coincided exactly with what I really wanted, for it was the union, within the phenomenon of grammaticalization, of the two components I am really interested in: semantics, and historical change. Thus I wish to warmly thank Jean-Pierre Nadal for having so insightfully set the topic of my PhD. Yet he did much more along the years, and taught me a lot of things, includ- ing economy in scientific prose, tolerance for other hypotheses which we may not like but are worthy nonetheless, and diplomacy in the research world. Most wonderfully, he never ran out of patience, despite my frequent stubbornness, and my systematic tendency to incline a little bit too much towards the Humanities. I would also like to thank Benjamin Fagard, who was not officially my supervisor in title, but endorsed the role anyway as if he really were. We discussed a lot, and I wish I had found the time, the strength and the skill to explore all the possibilities he mentioned along the lines. There were numerous ideas I could not dig deeper in, or that were left aside without any further notice, and for this I am sorry. I learned from him many exciting and fascinating things about language and linguistics, and I have never ceased to be amazed on how open minded, tirelessly curious, and communicatively enthusiastic he may be. I must also thank Mariana Estela Sánchez Daza, who closely followed this project, and provided me with an invaluable lot of advice, be it on the scientific or the personal planes, that I may not have always listened to, but which shaped anyway both the contents and the conduct of this work. I would have went on rampage in more than an occasion if she had not suggested me new perspectives and new ways to deal with the somewhat frustrating situations which abound in a PhD thesis; and discussing with her the concepts and the technical obstacles quite often helped me to accommodate the former and overcome the latter. To this long list I must also add that she proofread my thesis from start to end with great care and no less insight before I submitted it, which but deepens my abysmal indebtedness to her. I have also a most grateful thought for Tommaso Comparin, who have simply saved this thesis, and this is but an understatement. Any time I asked him a question on Python he answered me in full v vi ACKNOWLEDGEMENTS detail, providing all possible help one could imagine; in truth I could not have done half of what I did without him. He convinced me that I should treat data from corpora in an automatized way, which ended up saving me months, if not many more. The scale on which the semantic change has been analyzed is thus due to the persistence, the dedication, and the profound generosity of Tommaso. My own mother Isabelle has also earned more than a mention, for she, too, proofread this thesis, hunting down with sharpness and application my grammatical mistakes. If the reader might find some that have escaped her notice, it is ascribable only to my own hiding them in convoluted formulations in a language which is not my own. It would also be unfair to mention my mother and forget my father Karl, who constantly pushed me forward when I was on the verge of giving up, providing me with the strength and the heart to face the occasional hardship of this work. Also, Physics is to me the most entertaining conceptual playground I can think of, and if I got to join the field, a choice I never had to regret, it is entirely thanks to my father.