When the balance tilts from science to religion, the towers topple. Nothing so awe-inspiring had been seen in Europe for a thousand years, not since the days of the Roman Empire. Â But now Gothic cathedrals were towering above the horizon with stone spires that seemed to reach heaven. Â Their impossibly thin walls, filled with stained glass windows, allowed brilliantly colored light to flood vast interiors, capable of holding the population of an entire medieval city. Yet this revolutionary style of building that would dominate Europe for centuries seemingly appears out of nowhere. Â Now, an international team of engineers, architects, art historians, and computer scientists search the naves, bays, and bell-towers for clues to how the dream of these heavenly temples on earth came true.