Soul Health

 Rambam (Shemoneh Perakim (03) The ancients maintained that the soul, like the body, is subject to good health and illness. The soul’s healthful state is due to its condition, and that of its faculties, by which it constantly does what is right, and performs what is proper, while the illness of the soul is occasioned by its condition, and that of its faculties, which results in its constantly doing wrong, and performing actions that are improper. The science of medicine investigates the health of the body. Now, just as those, who are physically ill, imagine that, on account of their vitiated tastes, the sweet is bitter and the bitter is sweet—and likewise fancy the wholesome to be unwholesome—and just as their desire grows stronger, and their enjoyment increases for such things as dust, coal, very acidic and sour foods, and the like—which the healthy loathe and refuse, as they are not only not beneficial even to the healthy, but possibly harmful—so those whose souls are ill, that is the wicked and the morally perverted, imagine that the bad is good, and that the good is bad. The wicked man, moreover, continually longs for excesses which are really pernicious, but which, on account of the illness of his soul, he considers to be good.