Three Books on Life

...and the three powers original: "vires". In Renaissance medicine, these are the faculties of the soul that govern bodily functions. which we mentioned: namely the natural, the vital, and the animal original: "animalis". This refers to the "anima" or soul, specifically the faculty governing the brain, senses, and movement, rather than "animalistic" behavior.; by which, through which, and in which the spirits themselves are conceived, born, and nourished.

Scholars are prone to phlegm and black bile. Chapter 4.

Not only must those who are desirous of learning care most diligently for those limbs, powers, and spirits; they are also commanded to avoid phlegm original: "pituita". One of the four bodily humors, traditionally viewed as cold and moist. and black bile original: "atra bilis". The humor responsible for the melancholic temperament. no differently than sailors avoid Scylla and Charybdis Two legendary sea monsters from Greek mythology residing on opposite sides of a narrow strait; a metaphor for two equally dangerous threats.. For as much as they are idle in the rest of their body, so much are they busy in their brain and mind. Because of this, they are forced to produce phlegm (which the Greeks call phlegma) and black bile (which the same people call melancholia). The former often dulls and suffocates the intellect. The latter, however, if it should abound too much or become inflamed, vexes the soul with constant care and frequent delusions, and disturbs judgment. So it may be said not without merit that scholars would be remarkably healthy, were it not that phlegm is troublesome; and they would be the most joyful and wisest of all, were they not compelled by the defect of black bile to often grieve or sometimes act foolishly.

The reasons why scholars are, or become, melancholic. Chapter 5.

That scholars are melancholic happens because of three primary types of causes. The first is celestial; the second is natural; the third is human. The celestial cause is because Mercury—who invites us to investigate doctrines—and Saturn—who brings it about that we persevere in investigating and preserve what is discovered—are said by astronomers to be in a certain way cold and dry. Or if by chance Mercury is not cold, he nevertheless often becomes very dry due to his proximity to the Sun. Such is the nature of melancholy according to physicians; and Mercury and Saturn themselves impart this same nature to their followers, the students of letters, from the beginning; and they preserve and increase it daily. The natural cause, however, appears to be this: that to pursue sciences, especially difficult ones, it is necessary for the mind to [withdraw] from external [matters]...