Celsus,1 discussing the study of anatomy by the dissection of living criminals, a practice in vogue in Alexandria in the third century B. C., stated:
It is indeed true that the abdomen, with which our argument is less concerned, can be opened while a man yet lives, but as soon as the knife reaches the thorax, and cuts the transverse septum, which is a membrane dividing the superior parts from the inferior and called diaphragma by the Greeks, the man at once gives up the ghost and thus it is the breast and its viscera of a dead man and not a living man which the murderous physician examines. He had thus performed a cruel murder and has not learned what the viscera of a living man are like.
In this article we are not concerned with the results of opening the thoracic cavity. We are, however, interested in