In light of today's technological developments, the world has become more interested in everything that is quantifiable. In the field of architecture, this phenomenon has affected the design process, in terms of neglect human requirements related to the lived experience. This research is concerned with studying the intersection between what is quantifiable and what could contribute to improve the living experience. Research in disciplines such as art, architecture, and psychology assert that geometries with pure mathematical expression are visually pleasing. The present research aims to integrate these geometric relationships with daylight when formed by the edge of light and shadow, resulting from direct sunlight entering a room through roof openings and presenting on a northern wall. The goal of this research is to develop an initial prototype for a proof of concept that enables architects to consider humanistic, aesthetic criteria for geometry and daylight. The research progresses through three stages. First, the researcher describes a method to assess the geometry of lines resulting from the boundary between light and shadow when falling on a sunlit wall. Second, the researcher applies the described method to a random sample of roof opening configurations using digital modeling and a simulation of the sun's movement. Thirdly, the researcher extracts a regression equation that describes the relationship between the resulting shadow lines on the walls and the configuration of the roof openings. This regression analysis will form an initial step to developing a decision-support tool that predicts the purity of shadow lines during the early stages of the design process. / Doctor of Philosophy / Many architects acknowledge that the buildings we design today lack beauty. This research discusses the possibility of creating a program that considers visual beauty in architectural design. Many disciplines have offered praise about pure geometric shapes. The aim of this research is to develop a prototype that helps architects use these geometric shapes in architectural design specifically in the use of daylight inside rooms. To elaborate, when the sun moves, in its rising and setting, lines of shadows appear within the space that belong to pure geometric shapes. These pure forms are a source of visual beauty because they are derived from nature; as a result, our bodies have a physiological and psychological response when seeing them. The study is based on testing a hypothesis that asserts the higher the degree of purity of the lines used in the design of a room, namely the north-facing wall and roof openings, the higher will be the purity of the shadow lines resulting from the movement of the sun.