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Pluto doesn't even have a normal orbit! It is heavily tilted

And Venus rotates retrograde and one of the gas giants has an axis that is pointing almost directly at the sun. So they're all different for one reason or another. The writer of the opinion piece seems almost oblivious to the fact that "planet" is, indeed, an arbitrary distinction. It's a name given to a class of bodies that orbit the sun. If they're toward the big end, they're planets. If they're toward the smaller end, they're planetoids. If they revolve around another body that revolves around the sun, they're moons. Tiny Pluto was declared to be a planet because it was discovered in the course of a search for even farther out planets. So it's a planet because historically it was declared so from the beginning. So now we have the prospect of some rationalists going back over everything and trying to impose their own arbitrary definitions and thinking that they're talking about intrinsic properties.