Over the last years, several debates has open the issue on how to solve the social and economic conditions of the so called "third-world" countries and one opinion has driven the focus on how the improvement in health, education, science and trade should be under the responsability of the richer countries. This essay agree on this opinion revolving around two reasons: the current health of the "first-world" countries is due to 500 years of a colonial past and ecological and social justice.