If you didn't catch it, the line from the novel is among the riddles in the riddle game somewhere in the middle of The Hobbit by J.R.R. Tolkien. It's a prequel to the Lord of the Rings trilogy.
As for the entire riddle,
This thing all things devours
Birds, beasts, trees, flowers
Gnaws iron, bites steel
Grinds hard stones to meal
Slays king, ruins town
Brings high mountain down
Anyone want to *guess* the answer? (That means no one who's read the answer from the book.)
I think, therefore, I get bananas.
When in doubt, think about time travel conundrums. You'll confuse yourself so you can forget what you were in doubt about.
What's the difference between ignorance, apathy, and ambivalence?
I don't know and I don't care one way or the other.
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