The Libro de la anathomía del hombre is an exemplary case of a genre of medico-moral works that peaked in the Early Middle Ages and were still seen during the Renaissance. Although it is not, strictly speaking, an original treatise, it presents some relevant characteristics: it was the first anatomy treatise to be written in Spanish; epistemologically, it represents a turning point between Galenist and mechanist concepts of the body; whilst the medical discourse is configured as a true political treatise intended to legitimize the hegemonic order; and, in terms of style, the use of an allegorical dream allows us to treat it as an oneirological work.