Hypatia and her students ponder about the solar system and believe there is a simpler model for explaining it. A philosopher jumps in to explains the heliocentric model, as proposed by Aristarchus of Samos.
Hypathia incorrectly guesses how a sack will fall when it is dropped on a moving boat. She observes that the sack behaves as if the boat was stationary. Hypathia believes the same principle can be applied to the Earth: it is moving around the Sun without us realizing it.