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 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 tranquillity.