Inácio Vieira: Optics and Perspective. Instruments towards a sensitive space

Abstract

The manuscripts by Jesuit mathematician Inácio Vieira (1678-1739) played a significant role in the treatise production in Portugal. The Tractado da Óptica (1714) and Tractado de Prospectiva (1716) address the nature and properties of vision, the deception and disillusion of seeing and the fundaments of perspective. Geometric properties of visual rays, principles of optical illusion and values inherent to the optical and mathematical representation of space are explored, together with practical applications in architecture and painting. Although he does not make an original scientific contribution, he formulates operative statements applied to the arrangement of a sensitive space. This approach to optics and perspective highlights the relationship between reality and appearance in which the production of an image lies in the fact that, to show an object, one has to show it as it is not. Vieira’s work forges links between optics (perspectiva naturalis) and perspective (perspectiva artificialis), analyzing image distortion through spatial perception, illusion and quadratura. Pursuing an empirical architecture, the simulated space of quadratura is understood as a challenge that creates a new dimension and experience of architectural space. Form and metric properties, from real and illusory construction, are interrelated, contributing to an imaginary perception of spatiality. It is here that optics and perspective are established as architectural instruments to achieve a sensitive space.