An intentionally blank page is a page that is devoid of content, and may be unexpected. Such pages may serve purposes ranging from place-holding to space-filling and content separation. Sometimes, these pages carry a notice such as, "This page is intentionally left blank." Such notices typically appear in printed works, such as legal documents, manuals and exam papers, in which the reader might otherwise suspect that the blank pages are due to a printing error and where missing pages might have serious consequences. The phrase is a self-refuting meta-reference, in that it falsifies itself by its very existence on the page in question.
An intentionally blank page is a brilliant metaphor.
What do you think of when you see them at the end of a book?