Semantic A-translation and Super-consistency entail Classical Cut Elimination

We show that if a theory R defined by a rewrite system is super-consistent, the classical sequent calculus modulo R enjoys the cut elimination property, which was an open question. For such theories it was already known that proofs strongly normalize in natural deduction modulo R, and that cut elimination holds in the intuitionistic sequent calculus modulo R. We first define a syntactic and a semantic version of Friedman's A-translation, showing that it preserves the structure of pseudo-Heyting algebra, our semantic framework. Then we relate the interpretation of a theory in the A-translated algebra and its A-translation in the original algebra. This allows to show the stability of the super-consistency criterion and the cut elimination theorem

Talking Boulders: A Conversation with Maura Doyle

There’s a New Boulder in Town is Toronto artist Maura Doyle’s latest installation. With the assistance of University of Toronto geologist James Brenan, Doyle mapped a walking tour of some of Toronto’s ‘erratic boulders,’ and narrates their social-geological biographies through a guidebook

thumbpins, 2005-2006

In this project, I ask: are we at war for control of our security, our privacy, our identity? I began by using the fingerprint to intervene in the public sphere. I enlarged my own thumbprint and began leaving a silkscreened version of it in public spaces such as windows, and bus shelters. I went on to create silkscreened textiles with the thumbprint pattern, using an army green camouflage motif

Combattre par la plume : les écrits politiques soutenant la révolte des barretines (1687-1690)

Après avoir longtemps considéré les libelles comme des sources documentaires offrant un simple reflet de l’action ou comme les vecteurs d’un discours désincarné, les études consacrées à la littérature de combat se montrent désormais soucieuses d’aborder ces papers dans leur pleine spécificité. A partir du cas de la révolte des paysans Barretines en Catalogne (1687-1690), l’article veut montrer dans quelle mesure les écrits politiques des insurgés ont joué un rôle primordial dans ce conflit. Pour ce faire, il convient de les considérer comme des entrelacs de discours et d’action fortement contextualisés. Ces écrits sont modelés en creux par des pratiques politiques, sociales et culturelles spécifiques qui leur donnent une légitimité mais qui leur imposent des contraintes en retour. Le politique apparaît ainsi plus comme une praxis que comme un discours clos et autonome

if these textiles could speak, 2006 (in progress)

In this project, I examine issues of intimacy and surveillance and their relationship to sound and silence through textile production. I began by tapping my own phone, and recording phone conversations with willing intimates. I then used textiles to record these intimate conversations by embroidering the sound waves onto cloth. In this project, I am very deliberately my own surveiller. I am interested in the effect of surveillance and technology on intimacy and the relationship between public and private environments. What is security? How does knowingly being under surveillance affect my environment

the lies project, 2004-2005

This first work in the series is grounded by the idea that our world is made up of lies of all shapes, sizes, and persuasions, and that in fact these constructs bind our universe together. I began by collecting hundreds of donated lies at lying booths set up around Montreal. I then embroidered these in white stitch on white silk, in a font designed from handwriting. My interest in using the stitch was to weave the ephemeral quality of the lies, both materially and metaphorically, and to give the lies a life and immediacy through texture and image. I then treated the embroideries chemically, dissolving the silk fabric — their support — leaving behind only the stitch. The embroideries were then pinned, in single file, a string of lies just off the walls of a gallery

Performing Archives of Passing, Moving Bodies across Language

This experimental travelogue through process narrates research-creation work about an eighteenth century "multicrosser," Esther Brandeau / Jacques La Fargue, purportedly Jewish female passing as Christian male and the first (known) Jewish arrival to what is now called Canada. Outed on both counts and deported, this historical figure moved across many axes of differentiation simultaneously. This movement, these multiple simultaneous passings, and the fractured evidence that erupts this life into knowability, compel particular ways of working in order to translate from French colonial interrogation record into the colonial present. This paper describes the complexity of translating the first black box theatre work to contend with this story, ribcage: this wide passage by Heather Hermant, to French as thorax : une cage en éclats (trans. Nadine Desrochers). The author situates this practice-as-research within debates about body as archive and what constitutes knowledge; proposes performance-as-research as a realm in which a "new intersectionality" might best be elaborated; and body as translator/ion across languages and genres, temporalities and spatialities.En esta crónica de viaje experimental acerca de un proceso se narra un trabajo de investigación-creación entorno a la figura de Esther Brandeau / Jacques La Fargue, quien en el siglo XVIII cruzó múltiples fronteras: se trataba de una mujer judía que se hacía pasar por un varón cristiano, y fue a su vez la primera persona judía de quien se tiene registro de entrada al territorio ahora conocido como Canadá. Esther Brandeau / Jacques La Fargue fue, por estos dos motivos, víctma de delación y deportación. Esta figura histórica atravesó a la vez varios ejes de diferenciación; su movilidad, esos pasajes múltiples y simultáneos, y los trozos de evidencia fracturada que, al hacer erupción, dan su vida a conocer, requieren de acercamientos singulares para lograr traducir este personaje de los textos coloniales franceses al discurso colonial actual. El presente artículo describe la compleja tarea de traducir la primera obra de teatro estilo caja negra realizada para dar cuenta de esta historia. Se trata del montaje de Heather Hermant, titulado ribcage: this wide passage, traducido como thorax: un cage en éclats (trad. Al francés de Nadine Desrochers). La autora sitúa esta práctica-investigación en el marco de debates actuales acerca de qué constituye una forma de conocimiento y también entorno a la idea del cuerpo como archivo. Plantea desde su experiencia la idea del performance-como-investigación como un ámbito en el cual se logra elaborar una “nueva interseccionalidad”, y también la imagen del cuerpo como traductor-traducción entre distintos idiomas y géneros, temporalidades y espacialidades.Ce récit de voyage expérimental traite d’un projet de recherche/création sur Esther Brandeau / Jacques La Fargue, une juive qui se faisait passer pour un chrétien. À son arrivée au Canada, son double subterfuge a été découvert et on a déporté cette personne qui se déplaçait sur plusieurs axes de différenciation à la fois. Ce mouvement, ces déplacements multiples et simultanés et la nature fragmentaire de ce que nous pouvons savoir sur sa vie nous obligent à puiser à des modes de connaissance particuliers afin de pouvoir traduire ce personnage des textes coloniaux français en un discours colonial actuel. L’article décrit la tâche complexe de traduire le premier spectacle boîte noire traitant de cette histoire, ribcage: this wide passage par Heather Hermant (traduction française de Nadine Desrochers intitulée thorax : une cage en éclats). Cette pratique-recherche s’inscrit dans les débats sur « le corps comme archive » et sur ce qui compte comme connaissances; l’auteure propose la performance-recherche comme un terrain propice à l’élaboration d’une « intersectionnalité nouvelle » et à l’exploration du corps comme traduction entre genres et entre les frontières linguistiques, temporelles et spatiales.Este diário experimental de uma viagem por um processo narra uma obra de pesquisa-criação que lida com um “multicrosser” do século XVIII: Esther Brandeau/Jacques La Fargue, suposta judia que se passou por cristão e foi também a primeira pessoa judia (de que se sabe) que chegou ao território hoje chamado Canadá. Desmascarada em ambos os planos e deportada, essa figura histórica passou por vários eixos de diferenciação simultaneamente. Esse movimento, essas diversas dissimulações simultâneas, e a evidência fraturada que levou essa vida ao conhecimento, ditam maneiras específicas de trabalhar a fim de traduzir um registro de interrogatório em francês colonial no presente colonial. Este artigo descreve a complexidade de traduzir a primeira produção de teatro experimental que compete com essa história, ribcage: this wide passage, de Heather Hermant, para o francês, como thorax : une cage en éclats (tradução de Nadine Desrochers). A autora situa essa prática como pesquisa em discussões sobre o corpo como arquivo e o que constitui conhecimento, propondo a prática como pesquisa como sendo uma dimensão em que uma “nova intersecionalidade” pode ser melhor elaborada, e propondo o corpo como sendo tradutor/tradução através de línguas e gêneros, temporalidades e espacialidades

A simple proof that super consistency implies cut elimination

International audienceWe give a simple and direct proof that super-consistency implies the cut elimination property in deduction modulo. This proof can be seen as a simpli cation of the proof that super-consistency implies proof normalization. It also takes ideas from the semantic proofs of cut elimination that proceed by proving the completeness of the cut-free calculus. As an application, we compare our work with the cut elimination theorems in higher-order logic that involve V-complexes

Normalization by Completeness with Heyting Algebras

International audienceUsual normalization by evaluation techniques have a strong relationship with completeness with respect to Kripke structures. But Kripke structures is not the only semantics that ts intuitionistic logic: Heyting algebras are a more algebraic alternative.In this paper, we focus on this less investigated area: how completeness with respect to Heyting algebras generate a normalization algorithm for a natural deduction calculus, in the propositional fragment. Our main contributions is that we prove in a direct way completeness of natural deduction with respect to Heyting algebras, that the underlying algorithm natively deals with disjunction, that we formalized those proofs in Coq, and give an extracted algorithm