The influence of the final cause doctrine on anatomists of the sixteenth and seventeenth centuries concerning selected anatomical structures of the head and neck.

The Doctrine of Final Cause, taken from Aristotle's "causes" and modified by Claudius (Aelius) Galen (of Pergamon) stated that for an anatomical part to exist it must have a "cause," not an end point, but a purpose or goal, natural or divine. This affected the renaissance anatomist's thinking. We explore this doctrine's relationship with human head and neck anatomy from antiquity's Aristotle and Galen, and the leading renaissance anatomists from the 16th and 17th centuries. Their relevant writings were influenced by religious and political beliefs and varied from humanistic to reactionary. Tracing anatomical controversies through these works reveal the humanism of Vesalius and others as paralleling the humanists of art and literature. These controversies illustrate how the body was used to demonstrate function, uses, and causes from higher sources. Humanists advanced the social, philosophical, intellectual, literary, and medical/anatomical thoughts of this period. They stood between the Christian church of the Middle Ages and modern science. Like religion, medicine and anatomy had its own revealed sources of knowledge and had sacred texts like Galen's. Vesalius' the Fabrica and the woodcuts established suddenly the beginning of modern observational science and art as the direct and faithful representation of natural phenomena. They displayed anatomy such that others could understand, including errors of Galen, bringing Vesalius into ecclesiastical conflict. Evolutionary scientists today see mutations as favorable or unfavorable depending on the environment. Mutations are random or directed by divine plan, according to perspectives of this ancient debate.