O presente trabalho tem como objetivo investigar as fontes conceituais de um manuscrito anônimo tradicionalmente atribuído a Thomas Hobbes e conhecido na literatura como A short tract on first principles (Breve tratado sobre os primeiros princípios). Mostra-se, contrariamente à opinião dos principais comentadores, que a teoria física sobre a natureza da luz, elaborada na segunda seção do manuscrito, situa-se em um campo anti-aristotélico e está alinhada a uma perspectiva atomista, o que se evidencia a partir dos fortes e estreitos vínculos que a teoria mantém com as concepções corpuscularistas de Sir Kenelm Digby e de Sir Walter Charleton. / The aim of this work is to investigate the conceptual sources of an anonymous manuscript traditionally attributed to Thomas Hobbes and known on literature as A short tract on first principles. It shows, contrary to the opinions of leading commentators, that the physical theory of the nature of light, elaborated in the second section of the manuscript, is located in an anti-Aristotelian field and is aligned to an atomistic perspective, which is evident from the close and strong ties that the theory holds with the corpuscularianisms conceptions of Sir Kenelm Digby and Sir Walter Charleton.

O presente trabalho tem como objetivo investigar as fontes conceituais de um manuscrito anônimo tradicionalmente atribuído a Thomas Hobbes e conhecido na literatura como A short tract on first principles (Breve tratado sobre os primeiros princípios). Mostra-se, contrariamente à opinião dos principais comentadores, que a teoria física sobre a natureza da luz, elaborada na segunda seção do manuscrito, situa-se em um campo anti-aristotélico e está alinhada a uma perspectiva atomista, o que se evidencia a partir dos fortes e estreitos vínculos que a teoria mantém com as concepções corpuscularistas de Sir Kenelm Digby e de Sir Walter Charleton. / The aim of this work is to investigate the conceptual sources of an anonymous manuscript traditionally attributed to Thomas Hobbes and known on literature as A short tract on first principles. It shows, contrary to the opinions of leading commentators, that the physical theory of the nature of light, elaborated in the second section of the manuscript, is located in an anti-Aristotelian field and is aligned to an atomistic perspective, which is evident from the close and strong ties that the theory holds with the corpuscularianisms conceptions of Sir Kenelm Digby and Sir Walter Charleton.

This thesis argues that 17th century polymath Sir Kenelm Digby treats his scientific discourses as psychological romances in his works Loose Fantasies and Two Treatises, with his use of courtly romantic tropes, and that a contemporary audience would have read Digby's scientific treatises as literary. I first argue that science and romance in Digby's narrative romance Loose Fantasies are literary modes of the text's narrative form and that these modes are not mutually exclusive, since science is a "pyschodrama" to Digby, who is both the audience and author of these putative "private memoirs." I then relate Digby's "romantic science" in Loose Fantasies to his "poetike Idea of science" in Digby's Two Treatises in order to argue that while the treatise is traditionally received as a philosophical discourse, it is also a work of literary criticism. I conclude that Digby's "poetike Idea of science" is always unstable, because Digby cannot choose between the primacy of language and ideas in human cognition, due to the rapid rationalistic developments in epistemology during his time.

Dans le sillage des révolutions intellectuelles qui marquent l’avènement de l’époque moderne, Sir Kenelm Digby, catholique anglais, poursuit avec ardeur la connaissance du monde matériel et spirituel au gré des événements politiques qui ponctuent son époque tourmentée. À Londres comme à Paris où il est exilé, mais aussi au fil de ses nombreux voyages, Digby communique inlassablement des livres, échange des idées, et correspond sans relâche avec les savants de son époque comme Descartes, Hobbes, et Mersenne. Au sein du vaste réseau européen que constitue la jeune République des Lettres, il occupe une place de choix qui lui permet de produire une synthèse des idées en vogue. Digby participe à la sensibilité baroque que l’on définit non seulement par l’expression d’une crise liée à l’instabilité du monde et à la contradiction des choses mais aussi par la tentative de surmonter cette crise. Par ses intérêts variés pour l’alchimie, l’atomisme, la logique et la métaphysique, il tente de rendre compte, de façon baroque, du fonctionnement du monde et de l’homme afin d’en permettre la maîtrise et le gouvernement. Dans Two Treatises, il adopte et adapte l’hypothèse atomiste qui lui permet de dépeindre un monde fondamentalement chaotique, en changement permanent et agité d’une myriade de collisions invisibles qui expliquent la gravité et le magnétisme, mais aussi la reproduction ou la sympathie. Son approche démonstrative se veut un rempart contre la crise sceptique de son temps, et il ne cesse d’affirmer que la certitude est atteignable par les seuls moyens humains. Soucieux de prosélytisme, il met en relief la qualité orale de la tradition catholique et justifie la résurrection des corps, amenant au premier plan le sujet et ses perceptions, mais aussi la métamorphose comme principe explicatif clé. / In the wake of the intellectual revolutions of the early modern period, Sir Kenelm Digby, an English Catholic, endeavoured to increase the knowledge of the world, both physical and spiritual, against a backdrop of political turmoil. From London as from Paris, where he was in exile, the well-travelled Sir Kenelm sent books, communicated, and discussesd ideas tirelessly with the main thinkers of the time such as Descartes, Hobbes and Mersenne. His prominent place within the dense network of the incipient Republic of Letters allowed him to produce a seminal synthesis of the ideas then in circulation.Digby partook in the baroque sensitivity that we can define as the expression of a crisis linked to instability and contradiction, as well as the attempt to overcome it. Delving into alchemy, atomism, logic, and metaphysics, he strove to account for the secret workings of the world and of man in order to enable their mastery and government. In Two Treatises, he adopted and adapted the atomist hypothesis that allowed him to depict a deeply chaotic world, ridden with permanent change and fraught with innumerable and invisible clashes that explained all physical phenomena such as gravity, magnetism, generation, and sympathy. He aimed to proceed in a demonstrative manner so as to stave off the rampant crisis of scepticism, and he hammered through the idea that certainty was achievable by mere human means. In a proselyte effort, he tackled burning issues in the wake of the Reformation, promoting the oral quality of the Catholic tradition and the resurrection of bodies, while bringing forward the thinking individual and his perceptions, as well as the concept of metamorphosis, as key explanatory principles.