Why our interest in natural law still today? We can always criticize obligations and found human rights on the basis of natural law and we cannot accept a large gap between inclinations and desires on one hand and norms on the other. Natural law is not the lowest common denominator among men and is not always immediately apparent. We can find out it by a resolutio, going back from every day moral experience, from virtues and vices, from civil laws to the first principles. Natural law is the work of practical rationality, that makes order, looking with attention to reality and requires harmony between reason and inclinations towards perfect goods. Human desire is informed by reason and practical reason is always also speculative reason, because it knows reality. Desire “has eyes”, recognizing good. What goodness consists in is perfection. Since human being is open to infinity, the main and inclusive desire is desire for happiness and for God. Inclinations towards good are known, valued, interpreted by practical reason and they become moral norms thanks to the same practical reason.The normative dimension of law is also finalistic. The idea of conveniens is different from both Kantian and Utilitarian points of view. Ethical virtues are the flourishment of the seeds of natural law and there is no necessary opposition between freedom and natural law.