The two philosophers struggled to climb the hill under the pale glow of the crescent moon, their sandals crushing the parched ground below. As they approached the top of the mountain, the sky above exploded into a thousand flickering lights, the Milky Way stretching its ghostly arms through the darkness. Below, you could see the lit torches of the amphitheater, the crown jewel of Miletus. Anaximander wiped his sweaty forehead on his sleeve and smiled at his youngest pupil, Anaximenes. “Hard work pays off, doesn’t it? He said between two deep breaths.

Anaximenes gazed at the heavens in admiration. “Master, what do you think these lights are? Why do they stay up there, do they shine regularly? ” He asked.

“Watch carefully,” Anaximander asked. “You can distinguish different types of light. Some flicker and some don’t. Those that don’t flicker move slowly across the sky. These are the planets. To see that they move, you have to watch them for a long time. Months. Those that blink do not move. They are the stars. “

Anaximenes nodded. “But what is light? Is it the same as the sun? Or the moon?

Anaximander picked up a stick and drew a large circle on the sand. “It’s a very good question,” he said. “And until now, no one knew the answer. The ancients thought the lights were turned on there by the gods. The planets moved because of the gods. For them, everything that happened in nature was the work of the gods. of a god. Stupid superstitions if you would ask me. “

“Like Helios carrying the sun in his chariot every day, from east to west?” asked Anaximenes.

“Exactly. But how could anyone call this kind of explanation an understanding of the natural world? It’s just pretending to cover up our fear of the unknown. About what causes what. To say that a god has doing this or that doesn’t really work for me.

“So how do you explain the lights in the sky?” Anaximenes insisted.

“Well, look at this circle in the sand. The earth is right in the middle. Now imagine this circle is like a chariot wheel spinning around the center.” Anaximenes nodded. “Consider many wheels. One for the sun, one for the moon, some for the planets, and one for the stars. The cosmos is made up of wheels within wheels, revolving around the earth in the middle.”

“I have a headache imagining all those wheels turning up there,” complains Anaximene.

Anaximander smiles, drawing more concentric circles in the sand. “With practice, you can see everything with your mind. But there is more. These are not ordinary wheels. They are filled with fire. The lights that we see in the sky – the sun, the moon, the planets, stars – it’s just that fire that escapes from the holes in the wheels. When the wheels turn, we see the light turning too, always from east to west.

Anaximenes looked at his master, visibly troubled. “Do you mean the cosmos is like a machine?” Spinning wheels spitting fire through holes? “

Anaximander burst out laughing. “Exactly! No gods needed, only mechanisms. This is what the mind can do if we put it to work. We are physicists. We seek explanations in nature, not in gods.”

A rushing cloud momentarily covered the moon, creating a mosaic of light and shadow on the ground. “Things are fleeting,” Anaximander said. “Like the tides, everything comes and goes. Thales, my teacher, taught that water was the primordial substance, the essence of everything. But he was wrong. Better to go beyond these insignificant material things and postulate that all things come from the apeiron – the innumerable, the indefinite, the immaterial material principle of all things. “

“Does this mean that the indefinite contains both water and fire?” Asked Anaximenes.

– Yes and no, answered Anaximander. “It contains everything but not as we see it. It gives birth to everything again and, through transformations that we cannot see, fire, water, air and earth are created.”

Moonlight returned, illuminating the wheels on the sand. “Master, why can’t we see the wheels when we look up? Asked Anaximenes.

“Good question,” Anaximander replied. “Perhaps because the heavens are not transparent to the eye, and we can only see the brightest fire that escapes from the wheels.”

Anaximenes shook his head. “Or mm… maybe,” he stammered, “there are no wheels but crystalline spheres!” You see master, the crystal is transparent, and that’s why we can’t see it up there. the stars with them. But just the stars… I believe that the sun, the moon and the planets are carried by the winds, supported by the cosmic breath.

Anaximander looked at his student. For the first time, he saw him as an equal. “I don’t know what to make of your idea of ​​stars attached like nails to a crystal ball,” he said. “But you think like a physicist, and that’s all I want from you. A mature student should contradict his teacher.” Anaximenes smiles shyly.

“We better start going down, before we lose all the moonlight,” Anaximander said. “Tomorrow you will tell our friends about this conversation and our disagreement in some respects.”