If artists in the 15th century had learned to portray with faithful accuracy the human form through careful observation and anatomical dissection — a similar inspiration occurred to those seeking a corresponding dramatic reality in the representation of physical space. A means was devised early in the 15th century for translating the reality of 3-dimensional natural phenomena onto 2-dimensional surfaces, producing virtually realistic copies. A correspondence was thus made possible, through mathematics, between the representional reality of the artist and the physical reality of nature.

via Smarthistory, a multimedia web-book about art: discussing How Brunelleschi “Discovered” Linear Perspective.