De dolore disputatio medica

VIII.
Specifically, an unequal hot and cold intemperies. For pains occur in those things in which nature is changed and corrupted, not in those for which it is already corrupted. On the Causes of Symptoms 1.6. For even during the very act of changing, and in the process of becoming, all such things become causes of pains. On the Causes of Symptoms 1.6.

IX.
Although, therefore, a dry intemperies may be said by Galen to bring about pain, in Method of Medicine book 13, chapter 8, it is nevertheless deliberately omitted in this place.

X.
For just as humidity, by itself and in isolation, cannot bring about a sudden and violent change, so neither can dryness. For they are passive and material qualities.

XI.
But Galen says, in his commentary on the Book of Fractures part 34, that heat excites pain by penetrating and, as it were, eroding the continuous body: but cold does so by constricting those things which have been loosened.

XII.
Matter must be considered both insofar as it exists, and insofar as it is at fault.

XIII.
If it exists as something: it is a vapor, or a mineral, as they call it. Any vapor can be [a cause]: for it has the power to loosen continuity.

XIV.
A mineral is either animate or inanimate.

XV.
Of the former kind are worms generated in the intestines.

XVI.
That which is destitute of life is either contrary to nature in its whole genus, such as stones generated in the body: or it is not contrary to nature in its whole genus, and is either humor-like or spirit-like.