Leonardo da vinci's The Devil's Optic

 

The Devil's Optic

Date: 1509

Story:
In Florence, Leonardo constructed a device that mimicked binocular vision—an early prototype of what we’d call a stereoscope. It involved curved mirrors, lenses, and a rotating wheel with paintings mounted to simulate three-dimensional depth.
When he demonstrated it to a small group of scholars, one exclaimed: “This is not science—it is sorcery!” Rumors quickly spread that da Vinci had created an “optic that revealed the world of demons.”
The Dominican friars in Santa Maria Novella investigated. One brother, after viewing the device, reportedly saw a swirling red vortex and collapsed in fear, convinced he had glimpsed Hell.
Leonardo dismantled the device and burned the lenses. But he recorded the results in secret, noting that “perception is shaped by fear, and truth blinds those who are unready.”
To this day, some occult historians consider the device a spiritual portal disguised as scientific inquiry.

Key Characters:

Leonardo da Vinci
Dominican friars of Florence
Lorenzo de’ Medici’s science advisor
Anonymous witness to the test

Reference:

Codex on Vision and Light (lost, fragments cited by D. Imola, 1602)
Leonardo's Magic Machines by Carlo Pedretti
Oral accounts from Santa Maria Novella