Anton spoke with animated gestures, even drawing his wand to conjure a blackboard behind him and sketching the solar system on it.
But this diagram was completely different from the usual one. At its center was not the sun they had all grown familiar with, but Earth.
"Aristotle divided the universe into two regions: the supralunar and the sublunar."
"The supralunar region contains all celestial bodies beyond the moon. They are made of aether and revolve around Earth along fixed paths, which is why we can clearly observe sunrise and sunset."
"The sublunar region, at the center of the universe, is composed of four elements."
"Water, fire, earth, and air."
"Each of these four elements has its own characteristics. Water and earth tend to converge toward the center of the universe, and this tendency is stronger in earth than in water."
"So earth formed the planet, while water formed the seas, rivers, and lakes on its surface."
"Under this principle, when a stone falls into water, it sinks to the bottom. When a stone is thrown upward, it falls back toward the ground."
"Fire is the opposite. It moves away from the center of the universe, which is why we see flames rising."
"Air, meanwhile, moves toward the region between water and earth on one side and fire on the other."
As Anton explained, he made illustrations appear on the blackboard.
"At the same time, these four elements possess four qualities: dryness, wetness, coldness, and heat."
"Water consists of wetness and coldness, fire of dryness and heat, earth of dryness and coldness, and air of wetness and heat."
"They can change from one form into another."
"For example, when water encounters fire, its qualities change from wet and cold to wet and hot, transforming it into air."
"For example..."
"..."