Volunteers with no background in art theory were shown an original image of a sculpture, Doryphoros by Polykleitos (center) as well as distorted versions (left and right). The original obeys the golden ratio, a mathematical figure often found in nature that Renaissance artists thought embodied ideal beauty. The original activated certain sets of brain cells more than the distorted versions, suggesting the brain judges beauty by at least partly hard-wired standards. Credit: Cinzia Di Dio et al.