Galileo did not change the heavens. He changed how humans described them. When his telescope revealed a rough Moon and moons orbiting Jupiter, it exposed a gap between inherited ideas and the material world itself. That gap is the split: reality is one thing, our models of it another. Wisdom begins when we remember the difference.

Translated from early Italian, Galileo wrote the following in his Il Saggiatore (The Assayer) in 1623:

“Philosophy is written in that great book which ever lies before our eyes—I mean the universe.”