Medieval Filiations, Sameness, Otherness: Social Experiences and Representations of Kinship in cases of Defects of Filiation The manner in which medieval people thought about, experienced, and understood kinship in the Latin West (9th – mid-16th centuries) is at the heart of the Fil.IAM project. C. Avignon heads a programme of research on the social and cultural impacts of the hierarchy of filiation resulting from an “error of birth”. This canonical defectus, creator of legal incapacity, stigmatised illegitimate children with the stain of bastardy. Tensions led to the denial or degradation of filiations, as well as to strategies of secondary affiliations (nutritive and artificial), which will be compared to the issues of, as well as the reasoning and motives behind, exclusion and vulnerability in cases of other degraded forms of filiation linked to disabilities of infirmity or illness. The programme will insure that weak signals from sparse documentation will receive concerted, maximised treatment. At the same time, it will provide a fresh reading of medieval bastardy through a comparison between the expressions et representations of legal incapacity and those of bodily infirmities. A team of international collaborators will provide the programme with their expertise in digital humanities, their experience in epistemological and technical issues, and their mastery of these fields of study and corpus of documentation (thematic, jurisdictional, and chronological) in order to examine how identity markers were transmitted and circulated, to understand how processes of stigmatisation and individuation took place, and to reexamine the concept and experiences of filiation through an interdisciplinary approach. The goal is to insure that sources are collected which allude to the hierarchy of filiation, as well as to mobilise symbolic speech on kin relationships, in order to appreciate what bastardy did to western kinship. A tool will be created to analyse normative discursive productions and archives on the practice to grasp and process the semantic fields used to talk about, signify, or connotate the degradation of filial relationships. In order to appreciate the specificity of the social construct of bastardy, in regards to the impairment and disability of inhibited bodies, a doctoral contract is being financed to accompany research on the following subject: “Defects, Incapacity, Stain. Discours et representations of inhibited bodies in Christian society (12th-15th centuries).” The assessment of available sources and their promotion in the platform is a prerequisite to analysing the hierarchy of filiation, and the limits of prevented or degraded affiliation. The results will be examined within the framework of research encounters which will provide an overview of the historical analysis as well as the legal, literary, and anthropological issues at play in expressions of filiation in traditional societies. The project also defends the legitimacy of medievalist expertise in contemporary debates over western kinship and other forms of family networks, by putting the tensions at work (and their respective strengths) into historical context, between naturalisation of kinship and social construction, between identity and otherness. Exploring these questions from a medieval standpoint makes it possible to calm the terms of the debate, experience its deep historicity, and grasp the continuity, limits, or ruptures in the understanding and activation of blood relationships as well as the part of collective imagination built into the normative and symbolic hierarchisation of family relationships. It will accompany C. Avignon in a project of HDR deposit, then ERC.