Propositiones de lithiasi tōn nephrōn

VII.

The matter from which stones are made is, by the consent of all, a certain thick and earthy substance in some drying humor, as Galen in the cited places and Paul, book 3, chapter 45, agree.

IIX.

Most people hold this humor to be phlegm, since such matter is generally found in it, although Hippocrates in On Popular Diseases book 6, and Aetius in book 11, chapter 4, write that stones can also grow from both bile and pus if retained in the kidneys for too long.

IX.

That similar earthy matter is found in the serum, although it may appear thin, is declared both by the demonstration itself—that it can be separated by boiling and turn to stone—and by its saltiness; just as icicles, tufa, coral, and halcyonium sufficiently show that an earthy substance is present not only in seawater but also in the most limpid water.

X.

We do not hesitate to assert that this matter in the serum provides for the stones, although it may seem new to some.

XI.

In assigning the efficient cause, Galen is varied. For in one place he thinks the burning heat of the kidneys is required, as in On the Faculties of Nourishment 3, chapter 17 (which Alexander, Paul, and Aetius also affirm), elsewhere, as in Aphorisms 3, last, they think a milder and more remiss heat may suffice. Whichever we posit (for we believe that stones can be generated by both, although the former compounds the matter more quickly and the latter more slowly), this heat will be either innate or acquired.

XII.

Innate, as that which is hotter from birth or the principles of generation.