As a former US defence secretary, Donald Rumsfeld, above, once said: “There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don't know. But there are also unknown unknowns. There are things we don't know we don't know.” The Write Out Loud poetry writing exercise for April is: Write a poem entitled “Ten things I never knew I knew.”