126. Though the passions are physically good and in their nature morally indifferent, they may have physical reactions or moral consequences that are harmful or evil. These dangers may be physical, mental or moral. (a) Physical Dangers of the Passions.--It is a well-known fact that there is a close connection between the passions and the nerves, heart, and bodily organism in general, and that strong or persistent emotion can work great detriment to the health, producing disease, unconsciousness, or even death. (b) Mental Dangers of the Passions.--It is admitted by all that the passions disturb the judgment, and can even take away the use of reason. For they act upon the body or the senses, and these in turn affect the mind in a way similar to what happens in sleep or intoxication. Thus, love makes one blind to the defects of the object of one’s love; fear makes one magnify the evil of what is dreaded; melancholy unbalances the mind, etc. (c) Moral Dangers of the Passions.--It is likewise a matter of common experience that the passions are a source of many temptations and sins. Often they are antecedent (i.e., not premeditated or willed), as when they arise from bodily states over which one has no control or from imaginations strongly fixed in the mind, and at the same time tend to that which is not according to right reason, rebelling against the law of the mind. Thus, a person whose health is bad is easily dispirited, and this feeling occasions temptations to despair; one whose memory is haunted with the image of a lost parent becomes a prey to sadness, which makes it difficult to perform duties with zest and diligence. 127. A passion may become morally bad on account of the physical or mental evils connected with it. (a) Thus, a person has duties to his own well-being, and he indirectly wills (see 35 sqq., 94 sqq.) to neglect these duties, if he indulges harmful passions. Example: Sempronia grieves immoderately over the death of her mother, with the result that her health and mental vigor are impaired. (b) A person also has duties with respect to the life, health, and happiness of his neighbor, and he chooses to neglect these duties if he unjustly provokes emotions in others, foreseeing injurious consequences (see 96 sqq.). Examples: Titus so vexes Balbus by petty annoyances that the latter loses appetite and sleep, and becomes an invalid. Sempronia so exasperates her father by long-continued unfilial conduct that the latter becomes insane. Caius appeals to prejudices in order to have injustice done to a rival.