De dysenteria theses

XIII.
Which of the external causes has preceded it will be able to be understood partly from the report of the patient and those standing by, and partly from the constitution of the air and the sky.

XIIII.
Internal causes, if indeed the humors are sharp or salty, are easily revealed by the patient's temperament, the preceding diet, and the contemplation of what is excreted. If pus is the cause, it flows immediately at the beginning; afterward, the excretion of blood and shreds follows.

XV.
Since, however, it is of great importance for correctly establishing a cure to know whether the lower or upper intestines are ulcerated, this is diagnosed by the signs placed by Galen in On Affected Parts book 6, section 5.

XVI.
Therefore, if the blood which is excreted is mixed entirely with the excrement, it is a sign that the ulcer is in the upper parts. If it floats on top, it is in the lower. Let the judgment be the same for shreds and crusts.

XVII.
To these, add pain, which never departs from the affected place.

XVIII.
In long-lasting dysenteries, disgust for food is a bad sign, and even worse with fever (6. Aphorisms, 3).