Cats and humans have led a symbiotic existence for centuries, ever since man figured out that they were cute and cats realized that these tall bipeds were giving away free food and skritches. Cats have a way of making themselves the center of attention and ensuring they remain your top priority, not silly things like taxes or the mortgage payment, as shown by this fifteenth century book covered in inky kitty paw prints. Let us all have a moment of pity for this scribe, who copied a book out by hand – and then his cat walked on it.

Photo courtesy of Emir O. Filipovic.