Theou megaloio hekēti, Ad theses hasce de locorum affectorum cognitione generali

one definitely known, the other is also known.

X.

For just as a part is never harmed without the function also being harmed, so too is the function of no part harmed without that part itself also being harmed in some way.

XI.

And this is true not only in those affections which occur through idiopathia a primary, independent disease, but also in those which occur through sympathia disease transmitted between organs. Therefore, we correctly conclude: with vision harmed, the eye is affected; with digestion vitiated, the stomach suffers; with urine suppressed, the urinary instruments are tried; and similar cases.

XII.

For recognizing the affections themselves, fewer signs are taken from this source than for investigating the parts themselves; and they are taken by a certain secondary method, namely through the differences of the harmed actions.

XIII.

For vitiated digestion indicates that the stomach is affected. But the change of that which is not digested into an acidic or rank quality shows whether it is attacked by a hot or a cold affection.

XIV.

Opposed to sympathia is idiopathia, in which the cause of the disease resides, creating a permanent state.