Leonardo da Vinci examines the core principles that elevate painting from a mechanical craft to a genuine science. He begins by addressing the education of the young artist, stressing the absolute necessity of mastering linear and aerial perspective before attempting complex compositions. The text explores the exact proportions of the human body across different ages, detailing how muscles and joints contract and expand during motion.
A significant portion of the work is devoted to the mechanics of light and shadow, which da Vinci considers the true source of relief and three-dimensional form on a flat surface. He explains how to handle light from various angles, how to manage subtle demi-tints, and how to utilize reflexes to detach figures cleanly from their backgrounds. The author provides specific guidance on painting difficult natural phenomena, such as storms, dust, and smoke, while paying close attention to how atmospheric density alters colour at a distance.
Moving into composition and invention, the author outlines how to arrange figures to reflect specific mental states and emotions. He instructs the painter on achieving natural variety in faces, ages, and drapery folds, warning against repetitive gestures and stiff, unnatural postures. The treatise concludes with detailed observations on colour theory, the mixture of pigments, and the specific behaviour of light on different surfaces, offering a comprehensive manual for achieving truth to nature in visual art.
