How much our civilization is worth? Say, 10^20 dollars.

That's meaningless. You can't assign a value in dollars to the continued existence of our civilization. Dollars are only useful for pricing things inside that civilization. (Some people argue for using utilons to price the civilization's existence.)

If I had the money, I would be willing to part with 10^6 dollars to develop, manufacture, and distribute the book. Therefore, the probability of the book serving it's primary purpose is 10^(-14).

The amount you're willing to pay is a fact about you, not about the book's usefulness. You're saying you estimate its probability of usefulness at 10^-14. But why?