This article is a critique of the anthropology of vulnerability and of the needs on which the ethics of care are based. Firstly, this critique contrasts the universal postulate of the anthropology of vulnerability with the history of the anthropology of illness. The latter manages to build up a specific disciplinary field by refusing the supervision of the medical sciences and the implicit principle to consider illness as an universal fact. The paper refers to the anthropology of nature and Philippe Descola’s work in order to develop a comparative account of the systems of representations involved, including the naturalism of biomedicine as a model among others. It then presents the descriptions of the representations of vulnerability and the needs linked to the four main ontologies defined by anthropology of nature—animism, totemism, analogy, and naturalism—and gives a new light to the anthropology on which the ethics of care rest. That anthropology of vulnerability could be an involuntary factor making societies conform to an hygienic constraint. The ethics of care would therefore benefit greatly in freeing themselves from an anthropology of vulnerability and focusing on their original contextualism; in particular, they would benefit from an understanding of the limits of the naturalism at their basis. It will also allow them to offer a new tool for engineering social transformations at a time, the beginning of the twenty-first century, when cultures happen to mix.