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I think I have it from Ursula le Guin : one writes a book when one have an idea which couldn't be expressed in just few sentences (my free interpretation). My other guru author (see my Avatar

) compares book to a window into another world: you see only a fragment of it and that only through description - is that what you see enough to believe in it (free interpretation again).
What I want to say by it: in a book I like my fonts to be readable and my illustrations (if any) not distracting.
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