The open and shut door is an image used of the mind: the open and closed mind. An open mind lets things pass to and fro, while a closed mind shuts out both that without and that within. But a strong wind through an open door can send delicate things within flying or shut the door inadvertently, just as a strong experience can scatter or shut a mind or heart. Who within can reopen the door when the strong winds continue to blow against it? Who without will come to assist us if they cannot see what is on the other side of the door? That is the trouble with doors. A butterfly can pass through a closed gate but not a closed door.