Imagine the sensation of approaching and passing through the doorway in this photograph. Its dimensions are large enough to accommodate you comfortably; you can walk through easily, without stooping, brushing against the walls or turning sideways. And yet you sense thatfnsson as you go in. You know it is safe to enter but you are not quite sure what you will find inside. It is a sensation we all experience so often that, until reminded of it, we hardly acknowledge it.