why the differences occur. He considers the origin of kakochymia (literally, bad humors), listing the several sequelae that are essentially different forms of ulceration. He also considers the juice of the poppy, snake venom, the saliva of rabid dogs, and the cantharides. In particular, he deals with the heating and cooling effects of these substances.
4. Galen considers the distinction between things that are hot, cold, wet, or dry “of themselves” and those that are so “contingently.” He continues the differentiation between “in actuality” and “in potentiality” and what this involves in certain instances, for example, olive oil and wine. Detailed consideration is given to so-called deleterious or noxious drugs/medications, particularly in relation to time and amount of administration. He considers the reciprocal action of administered substances—what acts upon the body is also acted upon by the body, although the “reaction” may be imperceptible. The concept of “perpetual affection” is raised. The actions of lettuce are given particular consideration.
5. This section is basically about the evaluation of medications in the dyskrasias and particularly hotness and coldness. First, there is the question of whether the medication itself is hot (or cold or wet or dry), and if so, whether it is so in potentiality or in actuality. In assessing a substance, whether medication or food, it should be free of any acquired hotness or coldness before administration, and it should be tested against an absolute or extreme condition. The question of whether it acts in and of itself or incidentally should be addressed; the key determinants of this are the condition and the time. The use of cold water in tetanus is given as an example. Aspects of the
mechanism of causing change are considered, including the possible involvement of an intermediary. The example of the use of a cataplasm in inflammation is given. Galen finally refers to his works on medications and to his Method of Medicine for further details on these matters.
6. This is a short summary, focusing particularly on two things, using hot/hotness as an example. The first is the different ways in which the term is used, and the second, the distinction between actuality and potentiality. The same comments apply to the other three elemental qualities.