Final answer:
Leon Battista Alberti wrote the treatise 'Della Pittura' on perspective. He believed in using proportion systems in art. His treatise addressed urban planning and systems.
Step-by-step explanation:
Leon Battista Alberti wrote the treatise Della Pittura (or On Painting) in 1435, which is considered important because it was the first published work on perspective.
Alberti believed that proportion systems should be used to create harmonious and balanced compositions in art. He emphasized the use of mathematical principles to achieve aesthetic perfection.
In his treatise, Alberti addressed urban planning and systems, including the design of buildings and spaces. His ideas influenced the development of Renaissance architecture and city planning.