That's when you find out they only exist in your own head.

Any struggle for dominance had existed only in my head.

I wanted to talk about the differences that exist in your head.

Richard knew they could not be opened again without the book, and the book existed only in his head.

She didn't have to rush to print her work because it already existed in her head.

Were these scenes painted from life, or did the places exist only in the artist's head?

They are human beings, women who feel and suffer, not disembodied ideas existing only in your head.

I had no right to grieve for a loss which existed only in my head.

Leon exists on the page and in his own head.

The real question is: how could there not be - even if it exists only in somebody's head?