no doubt by looking around--he didn't know Newtonian mechanics and would not be able to predict a planet's location from its perturbation of other planets. He didn't even realize the planets had elliptical orbits.

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Todd (Bowie, MD, US, North America, Earth, Sol System, Vega region, Local Bubble, Orion arm, Milky Way Galaxy, Local Group, Virgo A Cluster, Virgo supercluster, the universe in which spock is clean shaven)

Quidquid latine dictum sit, altum sonatur.

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