Leonardo da Vinci's exotropia may explain his artistic genius, study suggests

A study published in JAMA Ophthalmology by Christopher W. Tyler, a research professor at City University of London and the Smith-Kettlewell Eye Research Institute in San Francisco, proposes that Leonardo da Vinci had intermittent exotropia, a form of strabismus. Tyler examined hypothetical self-portraits attributed to Leonardo, including the Salvator Mundi, Saint John the Baptist, and the Vitruvian Man, and observed a divergence in the pupils. This condition, which affects both eyes intermittently, would have allowed Leonardo to switch between binocular and monocular vision, potentially enhancing his ability to render three-dimensionality in faces, objects, and mountainous landscapes. The study adds to ongoing discussions about Leonardo's genius, following the record sale of the Salvator Mundi for $450 million at Christie's New York on November 15, 2017.