This chapter will analyze Hippocratic medicine using in particular the study of the Hippocratic Corpus. In the texts of the Hippocratic Corpus, medicine becomes pragmatic and secular, with theories to explain the natural causes of disease and discussions of medical practices and professional ethics. The chapter will discuss fundamental theoretical and ethical changes in medicine after Hippocrates. It is important to keep in mind that the Hippocratic Corpus is not the text of a single author, but rather a compilation of writings by many authors with similar characteristics to those of Hippocrates of Cos. Many treatises may have been lost in the fire that destroyed the Great Library of Alexandria, but a librarian saved and compiled about 60 medical writings, publishing them as the Hippocratic Corpus. Identifying which texts were actually written by Hippocrates is still a work in progress for historians, but the influence of the physician from Cos is clearly seen in the text of the Corpus. Before Hippocrates, as the book's final chapter observes, medicine and religion were closely linked. The people believed that illnesses had a supernatural cause or were divine punishments, so treatments consisted of going to temples and praying to the gods for help. However, Hippocratic medicine distanced itself from religion and Hippocratic writings held that all illnesses had natural causes. In fact, there is no mention of supernatural or magical properties in the treatments used by the Corpus writers. This secular approach is visible in the text of Airs Waters Places, chapter XXII: I too think that these diseases are divine, and all the others are also, none being more divine or more human than another; all are ali...... middle of paper......in medical history". Am J Med Sci 246, no. 2 (2013): 154-57. Langholf, Volker. Medical theories at Hippocrates: Early Texts and Epidemics. New York: de Gruyter, 1990. Longrigg, James. Greek Medicine: From the Heroic to the Hellenistic Age: A Sourcebook London: Routledge Chapman & Hall, 1998. Rebollo, Regina A. . “O legado hipocrático e sua fortuna no período gréco-romano: de Cós a Galeno”. . JR Soc Med 106 (2013): 288-92. Scarborough, John, Van Der Eijk, Philip J., Hanson, Ann and Siraisi, Nancy. . Boston: Brill, 2005. Steluac, Robert M. and Stalkas, “Galen and the Humorous Theory of Temperament.”. 2 (1991): 255–63.