What is health? What is it to be healthy? Our first answer must inevitably be the answer of St. Augustine, when confronted with the theoretical problem of time: “If no one asks me, I know the answer; if I want to explain it to the one who asks me, I do not know it.” In both cases the first sensation of one who aspires to theorizing is that of perplexity. I think, therefore, that this initial perplexity has its source in (...) two principal reasons, capable of reduction to these two assertions: first, the idea of health has a complex structure, and, second, the idea of health has a variable structure. Without a thorough study of this complexity and this variability, the construction of the medical anthropology that our historical level requires would not be possible. We will try to point out the fundamental lines of both. (shrink)