And this disposition of particular people to particular disorders is very common: for it relates to all perturbations; it appears in many vices, though it has no name.

Some are, therefore, said to be envious, malevolent, spiteful, fearful, pitiful, from a propensity to those perturbations, not from their being always carried away by them.

Now this propensity to these particular disorders may be called a sickness from analogy with the body; meaning, that is to say, nothing more than a propensity towards sickness.

But with regard to whatever is good, as some are more inclined to different good qualities than others, we may call this a facility or tendency: this tendency to evil is a proclivity or inclination to falling; but where anything is neither good nor bad, it may have the former name.
XIII.

Even as there may be, with respect to the body, a disease, a sickness, and a defect, so it is with the mind.