I was originally inspired for the game design when I saw the ancient pattern of interlocking circles, known as The Flower of Life. This symbol had been used in sacred art since Egyptian times, but was also studied by Leonardo da Vinci. I tried to make the game an expression of the fusion between art, science, engineering, and mysticism that Leonardo instilled into his work.
Here are a couple studies of the Flower of Life pattern from da Vinci's notebooks. I've been familiar with these 2 drawings since I did my original research for the game:
However, I recently came across another example of a Flower of Life study by Leonardo, shown below. Supposedly, it's from the collection of work known as the Codex Atlanticus.
This pic was on a Tumblr blog, Passenger. I was pleasantly surprised to find that it was an image I'd never seen before:
Da Vinci diagrammed 2 configurations (in the upper right corner) that are used in the game as "Secret Symbols" - the 'flower' & 'circle'.