They put their weight behind Brunelleschi, a man whose ideas sounded like madness to his peers. He proposed building a massive dome without any internal wooden scaffolding (centering), claiming he could make the structure support itself as it rose. Brunelleschi’s Innovations

When the dome was completed in 1436, it was the largest in the world. For the Medici, it was a triumph. The dome became a physical symbol of the "Medici Golden Age," visible from miles away, signaling that Florence—and the family that funded it—was the center of the civilized world.

Brunelleschi’s solution was a masterclass in physics and "thinking outside the box":

He laid bricks in a specialized zig-zag pattern. This transferred the weight of the bricks to the internal vertical ribs, preventing them from falling inward during construction.