As anyone who loves poetry will testify, when you learn a good poem, you make a good friend. You have a voice that will pop up in your head, whenever you want it, and say something beautiful and consoling and true. A poem can keep you going when you are driving on a lonely motorway, or when you are trapped on some freezing ledge in the Alps, or when you are engaged in any kind of arduous and repetitive physical activity, and need to keep concentration. When some disaster overwhelms you, or when you are feeling unusually cheerful – or when you are experiencing any human feeling whatever – it is amazing how often some line or phrase will swim to the surface and help to articulate your emotions, to intensify them or to console.