Substantial identity, or the premises of a project that speaks about us, and speaks to us. Because this project is based on our deepest identity. We're made of flesh and emotions. How do we outline what is intangible? How to manage to reveal and define "the quintessence" (ou the essence of...) an individual from shapes and colors? That's what this research suggests. Trajectories of men and women are identified through a questionnaire of 13 points, that put into light stages of the life cycle. Each question refers to a shape as an answer. This ranking is based on the "Arc en ciel" method , symbolised by 4 colors: blue, red, green and yellow. These fragments of identity made up of shapes and colors, create a singular image that will intimately represent the respondent.