The transmission of Greek thought to the Arabs in the course of the translation movement had a huge impact on the development of Arabic science in its formative period. Insofar as Arabic pharmacology is concerned we must mention by name three important Greek texts which were available in Arabic translations by the middle of the 9th century CE: first, the book entitled On Medical Matters by Dioscorides, an army doctor who lived in the 1st century CE; second, the book entitled On the Mixing and the Properties of Simple Drugs by Galen, a physician who lived in the 2nd century CE; and third, the book entitled On the Composition of Medicinal Drugs by the same Galen. These texts not only broadened the horizon of the Arabs for their actual contents, they also provided patterns of formal arrangement and scientific organization. During this time the Arabs also became acquainted with the so-called Summaria Alexandrinorum, a summary of sixteen books of Galen compiled around the year 600 CE in the medical school of Alexandria – this summary of Galenic writings introduced to the Arabs the concept of humoralism, which was to dominate all later medical and pharmacological theories

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