[19] Again, such discharges as settle in the eyes, possessing powerful, acrid humours of all sorts, ulcerate the eyelids, and in some cases eat into the parts on to which they run, the cheeks and under the eyes; and they rupture and eat through the covering of the eyeball. But pains, burning and intense inflammation prevail until the discharges are concocted and become thicker, so that rheum is formed from them. This coction is the result of mixture, compounding and digestion. Secondly, the discharges that settle in the throat, giving rise to soreness, angina, erysipelas and pneumonia, all these at first emit salt, watery and acrid humours, whereby the diseases are strengthened. But when they become thicker and more matured, and throw off all trace of their acridness, then the fevers too subside with the other symptoms that distress the patient. We must surely consider the cause of each complaint to be those things the presence of which of necessity produces a complaint of a specific kind, which ceases when they change into another combination. All conditions, then, resulting from heat or cold pure and simple, with no other power
1
as a factor, must cease when heat changes into cold or cold into heat. This change takes place in the manner I have described above. Moreover, all other complaints to which man is liable arise from powers.
2
Thus, when there is an out-pouring of the bitter principle, which we call yellow
bile, great nausea, burning and weakness prevail. When the patient gets rid of it, sometimes by purgation, either spontaneous or by medicine, if the purging be seasonable he manifestly gets rid both of the pains and of the heat. But so long as these bitter particles are undissolved, undigested and uncompounded, by no possible means can the pains and fevers be stayed. And those who are attacked by pungent and acrid acids suffer greatly from frenzy, from gnawings of the bowels and chest, and from restlessness.
3
No relief from these symptoms is secured until the acidity is purged away, or calmed down and mixed with the other humours. But coction, alteration, thinning or thickening into the form of humours through other forms of all sorts (wherefrom crises also and fixing their periods derive great importance in cases of illness)—to all these things surely heat and cold are not in the least liable. For neither could either ferment or thicken. †For what shall we call it? Combinations of humours that exhibit a power
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that varies with the various factors.
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† Since the hot will give up its heat only when mixed with the cold, and the cold can be
neutralized only by the hot. But all other components of man become milder and better the greater the number of other components with which they are mixed. A man is in the best possible condition when there is complete coction and rest, with no particular power
6
displayed. About this I think that I have given a full explanation.