Software's Retrograde Motion

Last night I was furiously googling for the name of the ancient device that models the geocentric view of the universe. It's cleverly composed of gears and concentric spheres -- with the Earth at the center -- that mechanically represent the motion of heavenly bodies as they pass through the sky.

I don't remember for certain, but it may be one of these:

• Armillary Sphere (Ptolemaic)
• Antikythera Mechanism

In particular, these devices make allowances for the apparent retrograde motion of the planets beyond the Earth's orbit: when you visualize the Earth at the center of the Solar System, these planets appear to move "backwards" part of the time. A useful geocentric model has to describe these motions predictably.

It's interesting to compare these ancient devices to software for a couple key reasons:

• They are monumental technical achievements; and
• They contain a lot more inherent complexity than they really needed to have

How many Armillary spheres have we built? How many are we building right now? In what ways could we change how we think about software, software projects, and the software industry that might free us from unnecessary complexity?