If you write a book and self-publish it, but no one buys it, are you considered a real author?

This is analogous to the “if a tree falls in the forest and no one hears it, does it make any noise?” questions, but a little different. The forest is subject to physical laws.

Say a person writes a book, publishes it himself (or a publisher prints it). No one buys it. No one reviews it. It just sits there untouched like a turd on the tarmac.

Is that person an author? Does someone have to read your stuff in order to make you an author? Where is the line between a ‘writer’ and an ‘author’?