The Culture of Peace understood as the synthesis concept - sum of human rights, democracy, disarmament and sustainable human development - demands, as a humanizing response of globalization, important efforts of educational systems towards the achievement of four world social contracts ( Lisbon Group, 1995): the contract of basic needs aimed at suppressing inequalities, the cultural contract aimed at promoting tolerance and dialogue between cultures, the contract of democracy aimed at a system of world government; and, the Earth contract to promote stable and lasting human development. To do this - remembering Juan Carlos Tedesco (2001) - learning to live together, one of the pillars of 21st century education, can not be maintained in the exclusive domain of merely rhetorical adherence.