䷂ Ornery Orrery

Look at this LEGO orrery, the video: how turning the crank moves the earth and the moon. It’s an analog celestial computer like the Antikythera mechanism. The only active gravitational causal powers are the ones that keep the model on the desk. Gears, not gravity, make the bodies move. But also the sizes are all wrong. Space is big. Planets are small. An orrery isn’t a scale model.

Take a look at this questionably vibe-coded example.

(Footnote. The textures were supplied by INOVE’s Solar System Scope. And I checked moonphases against Moongaint so as to roughly align the moon texture. Whether the fixed stars are at in their right places? I forget whether I checked, “Please excuse the crudity of this model, I didn’t have time to build it to scale or paint it.”)

The four quadrants show:

• Top-left: Orrery scale model of sun, earth, and moon.
• Top-right: Real scale model.
• Bottom-left: Sky view straight up from orrery scale earth.
• Bottom-right: Sky view straight up from the real scale earth.

Notice how the sun and moon are huge in the orrery scale sky and tiny in the real scale sky, hence why it’s hard to take good photos of the moon. Both moon and sun are about half a degree, the same size in the sky, hence total eclipsis. What a coincidence and a temporary one at that!

An orrery doesn’t just use different causal powers, it barely simulates the solar system at all. What good is it? It maintains alignment. It preserves relative rotation. The phase of the moon should be about right for any given date. And for seeing the moon phase on a desk sized model, maintaining scale is a mistake since the moon would be too small to see. Simulation is sometimes better than duplication.

(Mr. Well Actually wants to interject that in space you could “in theory” make a scale model of the solar system that uses gravity as the causal power by maintaining relative masses and distances. You increase speed by either reducing distance or increasing mass. Thank you Mr. Actually.)

Maybe causal powers aren’t so simple. Material cause isn’t the most relevant. Something like formal cause is. What matters most is being situated in the right relationship to the right relevant thing.