Chauliac's book is confessedly a compilation. He has taken the good wherever he found it, though he adds, modestly enough, that his work also contains whatever his own measure of intelligence enabled him to find useful (_quae juxta modicitatem mei ingenii utilia reputavi_). Indeed it is the critical judgment displayed by Chauliac in selecting from his predecessors that best illustrates at once the practical character of his intellect and his discerning spirit. What the men of his time are said to have lacked is the critical faculty. They were encyclopedic in intellect and gathered all kinds of information without discrimination, is a very common criticism of medieval writers. No one can say this of Chauliac, however, and, above all, he was no respecter of authority, merely for the sake of authority. His criticism of John of Gaddesden's book shows that the blind following of those who had gone before was his special _bete noir_. His bitterest reproach for many of his predecessors was that "they follow one another like cranes, whether for love or fear, I cannot say." Chauliac's right to the title of father of surgery will perhaps be best appreciated from the brief account of his recommendations as to the value of surgical intervention for conditions in the three most important cavities of the body, the skull, the thorax, and the abdomen. These cavities have usually been the dread of surgeons. Chauliac not only used the trephine, but laid down very exact indications for its application. Expectant treatment was to be the rule in wounds of the head, yet when necessary, interference was counselled as of great value. His prognosis of brain injuries was much better than that of his predecessors. He says that he had seen injuries of the brain followed by some loss of brain substance, yet with complete recovery of the patient. In one case that he notes a considerable amount of brain substance was lost, yet the patient recovered with only a slight defect of memory, and even this disappeared after a time. He lays down exact indications for the opening of the thorax, that _noli me tangere_ of surgeons at all times, even our own, and points out the relations of the ribs and the diaphragm, so as to show just where the opening should be made in order to remove fluid of any kind. In abdominal conditions, however, Chauliac's anticipation of modern views is most surprising. He recognized that wounds of the intestines were surely fatal unless leakage could be prevented. Accordingly he suggested the opening of the abdomen and the sewing up of such intestinal wounds as could be located. He describes a method of suture for these cases and seems, like many another abdominal surgeon, even to have invented a special needleholder.