This dissertation presents the foundations of representation and knowledge on René Descartes Meditations in order to discuss his project on the reconstruction of the whole science of his time through a critical review of it s underpinnings. We approach the theme through the analysis of the six meditations, beginning with doubts concerning opinions and sensitive knowledge in general, as well as doubts about the subject's own knowledge in particular. Analysis is made of the means that lead to the first certainty, the one which concerns the thinking subject, which is aware of its own existence and whose synthesis is manifested in the expression: "I am, I exist", which serves as a background for the other findings, such as the existence of God and its truth, the problem of representation, or the representative character of ideas, of their objective reality, and the principles of causation and correspondence. We also highlight the importance of statements about the ability to analyze, which implies the possibility of error when a statement is set out without proper verification of it s clarity and evidence, for the acts of thinking, wanting, desiring, are always true, but the judgments based on them may be misleading, if their foundation does not satisfy the criteria of clarity and evidence. / Esta dissertação apresenta a fundamentação da representação e do conhecimento, a partir da obra Meditações, de René Descartes, com o intuito de discutir o seu projeto de reconstruir a ciência, a partir da crítica das opiniões que fundamentavam a ciência de seu tempo. A abordagem do tema se dá a partir da análise das seis meditações, iniciando pela dúvida acerca das opiniões e do conhecimento sensível de um modo geral, bem como do próprio sujeito do conhecimento, de modo particular. São analisados os meios que levam à primeira certeza, a do sujeito pensante, que tem consciência da sua própria existência e cuja síntese se manifesta na expressão: eu sou, eu existo , a qual serve de ponto de apoio para as demais constatações, como a da existência de um deus e de sua veracidade, do problema da representação, ou do caráter representativo das idéias, da sua realidade objetiva, e dos princípios de causalidade e de correspondência. Destacamos também, a importância das afirmações sobre a capacidade de ajuizar, o que implica na possibilidade do erro quando um juízo é enunciado sem a devida constatação de sua clareza e evidência, pois os atos de pensar, querer, desejar, são sempre verdadeiros, mas os juízos deles decorrentes podem levar ao erro, caso o seu fundamento não obedeça aos critérios da clareza e da evidência.

Le but de cet essai est d’interroger la questionne de la langue, en tant qu’outil privilégié dans la communication humaine, dans son rapport avec l’existence de l’être humain et de faire le point sur le débat, plutôt littéraire, se rapportant sur les aspects convergents et divergents entre les moyens d’expressions chez l’être humain et l’animal. La langue est l’un des éléments le plus manifeste dans la vie de l’être humain mais elle est tellement évidente qu’on a souvent tendance à l’écarter dans les débats concernant les phénomènes humains. De même, mis à part certains auteurs qui se sont penchés sur la question de la langue, ce sujet fait rarement objet de choix de ceux qui se donnent pour tâche d’approfondir les œuvres des hommes et femmes littéraires et les œuvres philosophiques françaises. En fait, on a beaucoup parlé de Montaigne, Pascal, Descartes, et Rousseau ; mais l’aspect de la langue dans les œuvres de ces auteurs est sous exploré. Néanmoins, c’est un sujet qui est encore à examiner et qui, en fait, joue un rôle prépondérant dans les œuvres de Montaigne, Pascal, Descartes et Rousseau. En entamant ce débat on n’est pas sans savoir que les archives littéraires et philosophiques françaises sont multiples et divers. Il serait donc utopique de vouloir entreprendre une revue exhaustive de la question de la langue dans les œuvres des auteurs français. Les discussions dans cet essai sont basées notamment sur une partie des œuvres de Montaigne, Descartes, Pascal et Rousseau. En particulier, ce dossier esquisse une revue critique des points de vue de Montaigne et Descartes sur l’animal et l’être humain par rapport à la communication, le duel entre Pascal et Montaigne et les points de vue exprimés par Rousseau concernant la langue. Ce dossier conclut avec un penchant sur Descartes qui établit une relation étroite entre la pensée, la langue et l’existence de l’être humain. Abstract (English Version) The purpose of this study is to interrogate the question of language as related to human existence and to delve into the literary debate with regard to the relationship between the ways human beings communicate among themselves and the way animals express themselves to each other. Language is one of the most important aspects in the life of human beings. It is so evident in our daily activities that one often has the tendency to neglect it in debates that surround the many phenomena that are influential in the existence of human beings. Likewise, scholars interested in the works of the French thinkers rarely examine the role that debates on language play in their writing. In fact, the works of the French authors Montaigne, Pascal, Descartes, and Rousseau are broadly known both in the milieu of French and Francophone Studies and other branches of knowledge such as the Humanities, the Social Sciences, and even the Mathematics. However, debates related to language in the work of these authors have not been explored sufficiently. Given what language represents for human beings, it is a subject that should continue to occupy an important place in the reflections of the academic community. The works of these authors i.e. Montaigne, Pascal, Descartes, and Rousseau offer grounds on which one can raise important debates related to language. This study draws on the works of Montaigne, Pascal, Descartes, and Rousseau to interrogate the issue of language as related to human existence and to discuss whether language is a phenomenon exclusive to human beings or if it is a shared attribution between human beings and animals. In particular, this study makes a critical review of the viewpoints expressed by Montaigne and Descartes on the relationship between human beings and animals with regard to communication, the conflicts between Pascal and Montaigne, and the viewpoints expressed by Rousseau with regard to language.