Sistematização da Ciência Perspética: fontes e enunciados teóricos nos Tratados da Ótica e da Perspetiva de Inácio Vieira

Abstract

The article examines the geometric procedures, at the basis of the delineation and projection of the Quadratura image, throughout the statements, notes and schemas present at the Tractado de Óptica (1714) and Tractado de Prospectiva (1716), both written by Inácio Vieira (1678-1739). The Jesuit mathematician, lecturer at Lisbon’s Aula da Sphera, orders the manuscripts in a clear progression since the recognition of the sight and properties of the retina’s image from which are structured the possibilities of its graphical interpretation, oriented under values of geometric-mathematical nature, as well as methods to manoeuvre visual experience. A sequence amplified by acknowledge of light reflection and refraction undertaken at the Tractado da Catóptrica (1716) and Tractado de Dióptrica (c. 1717). Dealing with Perspective, both natural and artificial, the manuscripts follow a practical and systematic model oriented towards its application, namely by architects and painters, in which are assimilated and ordered contents from coeval European treatises. As such, Vieira's texts on Optics and Perspective are here examined in order to fully recognize its structure and thematic areas, identify sources, and, with a particular emphasis, explore the expressed statements and graphical schemes in order to expose the necessary procedures to the delineation and projection of the Quadratura, at the pursuit of the illusion provided by the Imaginary Architectures.