This chapter begins with an analysis of “impartiality” within international humanitarian law and focuses on the contribution of Jean Pictet. It addresses the question of colonial differentialism and the late universalization of needs. In the colonial territories, the quantification of needs only targeted a handful of categories of persons: Soldiers, workers, and settlers. Jean Pictet outlined seven fundamental principles of humanitarian aid: Humanity, equality, proportionality, impartiality, neutrality, independence, and universality. He fully reworked the principle of “impartiality” by adding to it the principle of the proportionality of aid. Two fields of knowledge especially had turned “needs” into an object of scientific inquiry and bureaucratic quantification between the end of the nineteenth century and the 1940s: Political economy and health care. Pictet appealed to different logics of prioritization of needs – including rationing and medical care in times of scarcity. The notion of “needs” itself obviously had a much older origin within political economy.