PASSIONS, in medicine, make one of the non-
naturals, and produce very sensible effects. Joy, anger,
and fear, are the principal. In the two first, the spirits
are hurried with too great vivacity; whereas, in fear
or dread, they are as it were curbed and concentrated:
whence we may conclude, that they have a very bad
effect upon health; and therefore it will be best to
keep them within bounds as much as possible, and
to preserve an inward serenity, calmness, and tran-
quillity.