Leon Battista Alberti defines the Beauty of Architecture “a concert of all the parts together, performed with proportion and logic in something in which it is possible to find again each event, in a modality that will not allow the inserting, extracting out or changing anything without decreasing its Beautyi. With generative art we can approach, directly, this complex paradigm of proportions and logic, and we can directly design the Beauty, or better our idea of beauty, before the realization of each single possible artificial event. This is the heart of generative approach. The Generative Art work for the beauty, in the sense of the humanistic approach of Renaissance, because the generative code, which is the project of generative design, is the real structure of the idea. It defines how to concert all the parts and the dynamic relationship among these parts in the evolution of complexity. The generative project defines which is the law of proportion and which logic the dynamic evolution will follow. All the events that this code can generate will be, in humanistic sense, beautiful, or, if we prefer, will belong and represent our Idea of world. And more. The generative art produces events that are unique and complex. The uniqueness and complexity are strongly related one each other. As in Nature, each event is generated through an artificial life, which, as in the natural life, produces uniqueness, identity and complexity during a identifiable time. This complexity is a natural-like complexity. We can recognise, in the artificial ware we produce through this generative approach, the harmony and the beauty of the natural-like complexity that refers to the Humanistic approach of Renaissance: Man, Geometry, and Nature as references for “the harmony which is not thought as an individual caprice but as conscious reasoning.i (L.B.Alberti, De re aedificatoria).