But there is another Leonardo. A Leonardo of obsessive curiosity, of messy reverse-script handwriting, and of questions so vast they stretched the limits of 16th-century science.
He argued that the fossils were proof that the mountains had once been the beds of ancient seas, lifted up over incredibly long periods of time. He realized the Earth was ancient, shaped by slow, relentless processes like water erosion—not a single catastrophe. This put him centuries ahead of modern geology. If you ever get the chance to see the Codex in person (it travels occasionally), you’ll notice something odd. The text is written in Italian, but it’s backwards—from right to left.
Why does water swirl down a drain? Why do mountains look blue in the distance? Why is the sky blue? the codex leicester
Leonardo was left-handed, and it’s believed he wrote this way to avoid smudging wet ink as his hand dragged across the page. To read it, you literally have to hold the page up to a mirror.
And it just so happens to be one of the most expensive books on planet Earth. Despite the fancy name, this isn't a dusty medieval poem. It is a 72-page scientific notebook written entirely by Leonardo between 1506 and 1510. It is a firehose of genius, covering geology, astronomy, optics, hydrodynamics, and paleontology. But there is another Leonardo
Leonardo said: No.
In one paragraph, he jumps from the flow of a river to the cratering of the moon to the growth of a tree. He saw no barrier between art, science, and nature. To him, the curl of water in a fountain followed the same mathematical rules as the curl of hair on a human head. You don’t need $30 million to think like Leonardo. You just need a notebook and a willingness to ask dumb questions. He realized the Earth was ancient, shaped by
Leonardo wrote the Codex Leicester because he couldn't not know. He wasn't trying to publish a book; he was trying to talk to himself about the universe.