An interesting discussion sparked in the Russian Stack Overflow chat: a user mentioned that it is ambiguous whether the original title of the book (Трудно быть богом) is a question or a statement.
I replied that this form is most often used for statements, and is unlikely to be used as a question (to be clear, we're discussing the phrase now, not the book title); however, it occurred to me that this could be used as a question in spoken language, similar to
I do know that it requires a question mark at the end to be a real question, and I do know
трудно ли быть богом? is much better. For the record, Russian is my mother tongue. However, I don't have much experience with formal texts (haven't studied Russian since 7th grade).
My main concern is - can this form of a question be used in formal or written Russian? How acceptable is it?
1: Everyone is welcome to participate! Ask your Hard to be a God questions, and post good answers to others' questions!