What makes a book to be.... book?

I am not sure what exactly I should say for  Denis Guidone's project named "my book". I found it well designed, but it's idea was the fact that made me consider, what exactly is a book? The words? Or anything else?

This is a book without words. And it is not a journal or a sketch book. It is just a blank book. You can right it if you want, you can leave it as it is, blank. Whatever you do - or don't do- this is and will be a book. You wander why? Because the designer decided it. 

So finally, I realized that a book is not just the contains but the idea. When the creator want to do something, he just need to name it. Guidone gives a title to a pack of white pages, and suddenly create a book! Isn't it fantastic?

This is what he said about his creation:

"It is a book without text, at first sight might seem a misprint, but it is a pretext to imagine a story, a book that you could write yourself, day after day. It is a white space to imagine. You can also leave the pages blank and fill them in with simply your thoughts...

You will wonder: "in the "end"", what is it really? There is no end, perhaps it is only an object that will leave you simply "speechless". Here! this could be a really good start..."

Last but not least, I should say that the design is perfect. It is simple, but exists.

As the idea.