Official answer: "The inspiration for Ludovico Einaudi's I Giorni was a 12th-century folk song from Mali about a hippopotamus who was cherished by the residents of a nearby village but killed by a hunter. 'The song,' writes Einaudi in his succinct liner note, 'is sung as a lament for the death of a king or a great person or for the loss of a loved one.' The result is a tender and introspective set of 14 piano pieces. This work was written after Einaudi heard the kora playing of Toumani Diabate whilst travelling in Mali."
Unofficial answer: "Hippo was a cryptic message, for a person but I did not think that all these people would have seen this video, I didn't think that all these people (in the world!) knew Ludovico Einaudi :D"
... sorry for my English.
