There are a lot of mental defects which cause that illness, but the chief part is played by imaginary suspicion, which, if long nurtured, brings the mind into communities of similar spirits, from where it is difficult to extract it. This imaginary suspicion also strengthens itself in the body, causing the serum and hence the blood to become viscous, sticky, thick, slow-moving and acid. A loss of strength also increases it, for this prevents the mind rising above the suspicions it harbours. For the presence of strength exalts the mind, its absence depresses it. This makes the mind sink, collapse and become weak; and it then plunges more and more into that imaginary suspicion, until it becomes demented. The result of this is to take pleasure in quarrelling and unrestrained vilification.