The classification of human rights in “generations”, habitual in legal litterature, looks inappropriate in light of the consideration that human rights are inherent in human beings and do not depend on their recognition under the law, which is only relevant for their protection, as it clearly derives from the 1948 Universal Declaration. Furthermore, the Declaration refers to diffused rights of the so called third generation (right to peace, to development, to environment) under a provision on a social and international order, which leads to deny their nature as rights and to conclude that they should rather be qualified as duties aimed at ensuring the exercise of human rights. Finally, a diachronic reading of the universal nature of the Declaration implies that such duties comprise an international guarantee of human rights not only of the present, but also of future generations of human beings.