A man just moved into a house. Amid the chaos inside he heard a knock at the front door. He flung the door open only to find no one there. With a muttered curse, the man started to slam the door when he spied a snail on the stoop. Exasperated, he picked it up and threw it as far as he could.

A year later there was another knock on the door. The man opened it and the snail, with its hands on its hips, said impatiently, “Now, what the heck was that all about?”