...the trouble about arguments is, they ain't nothing but theories, after all, and theories don't prove nothing, they only give you a place to rest on, a spell, when you are tuckered out butting around and around trying to find out something there ain't no way to find out...There's another trouble about theories: there's always a hole in them somewheres, sure, if you look close enough.
- Tom Sawyer Abroad
How empty is theory in the presence of fact.
- A Connecticut Yankee in King Arthur's Court
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