theories represent the beginning of science as much as its endpoint. Theories tell us what questions to ask (“Why is Uranus’s orbit out of whack?”), what kind of answers to look for (“Something really big must be exerting a gravitational pull on it.”) and where to find them (“According to Newtonian calculations, that big thing must be over there.”). They also tell us what not to look for and what questions not to ask, which is why those astronomers didn’t bother looking for a giant intergalactic battleship warping Uranus’s orbit instead. These are invaluable directives, prerequisite to doing
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