VATICAN CITY, VATICAN - JUNE 18:  Orthodox metropolitan of Pergamon John Zizioulas and Cardinal Peter Appiah Turkson (R) present Pope Francis' encyclical 'Laudato Si' at the Paul VI Hall on June 18, 2015 in Vatican City, Vatican. The Pontiff a first encyclical is focused on the idea of "integral ecology", connecting care of the natural world with justice for the poorest and most vulnerable people. The leaked version of the document had already been criticised by Jeb Bush, the US Republican Presidential candidate.  (Photo by Vatican Pool/Getty Images)