Fracastorius considers it worth investigating why they entertain such false notions as having horns or great noses, or being birds or beasts, and why they think themselves kings, lords or cardinals. For the first, Fracastorius gives two reasons: the disposition of the body and the occasion that prompts the imagination, as when their eyesight is dim or their ears ring because of some cold or rheum. To the second, Laurentius answers that imagination, stirred from within or without, presents the understanding with more than inducements to favour the passion or to dislike: intense pleasure follows the passion, or displeasure does, and will and reason are taken captive by delighting in it.

The philosopher of Coimbra gives this reason why students and lovers are so often melancholy and mad: by intense and continual meditation on whatever affects them, they draw the spirits up into the brain; and with the heat these bring, they inflame it beyond measure. The chambers of the internal senses lose their balanced constitution, and once that is lost, they cannot perform their functions as they should.

Why melancholy people are intellectually gifted, as Aristotle long ago maintained in his Problems, and why learned men, famous philosophers and lawgivers have always been melancholy—“almost all, to a man, melancholic”—is a much-disputed question. Jason Pratensis takes this to mean natural melancholy, an opinion to which Melanchthon inclines in his book On the Soul, as does Marsilio Ficino in On Preserving Health, book 1, chapter 5. But not the unmixed humour: being cold and dry, that makes people stupefied, heavy, dull, fearful, foolish and solitary. It must be mixed with the other humours, except phlegm, and these must not be scorched; rather, blood should make up half the mixture, with little or no scorching, so that they are neither too hot nor too cold.

Aponensis, cited by Melanchthon, thinks it proceeds from scorched melancholy, excluding all natural melancholy as too cold. Laurentius rejects this doctrine because scorching the humours makes people mad, just as lime burns when water is thrown on it. It must be mixed with blood and somewhat scorched; and so that old aphorism of Aristotle may be confirmed: “No great intellect without an admixture of madness”—no excellent mind without a mixture of madness.

Let Fracastorius decide the controversy. Phlegmatic people are dull; sanguine people lively, pleasant, agreeable and merry, but not intellectually gifted. Choleric people are too quick in their movements and furious, unable to endure contemplation, with deceptive minds. Melancholy people have the finest minds, but not all of them: this humour may be hot or cold, thick or thin. If too hot, they are furious and mad; if too cold, dull, stupefied, timid and sad; if temperate, excellent, tending towards the extreme of heat rather than cold.

This judgment agrees with that of Heraclitus: a dry light makes a wise mind. Moderate heat and dryness are the chief causes of a good intellect. Therefore, says Aelian, the elephant is the wisest of all brute beasts, because its brain is driest, and “because of its abundance of black bile”; Cardan approves this explanation in On Subtlety, book 12. Giovanni Battista Silvatico, a physician of Milan, has discussed this question extensively in his first controversy; so have Rulandus in his Problems; Caelius Rhodiginus, book 17; Valleriola, sixth Medical Narrative; Hercules de Saxonia, posthumous Treatise on Melancholy, chapter 3; Lodovicus Mercatus, On the Treatment of Internal Diseases, book unspecified, chapter 17; Baptista Porta, Physiognomy, book 1, chapter 13; and many others.

Weeping, sighing, laughing, itching, trembling, sweating, blushing, hearing strange noises and seeing visions, wind and indigestion are bodily movements depending on these preceding movements of the mind. Tears are not affections but actions, as Scaliger holds. The voice of those who are afraid trembles because the heart is shaken (the Coimbra commentary, problem 6, section 3, On Sleep). Mercurialis and Montaltus, chapter 17, give similar explanations from Hippocrates for stuttering or faltering in speech: dryness makes the nerves of the tongue torpid. Rapid speech, a symptom in a few, Aetius attributes to abundant wind and quickness of imagination. Baldness comes from excessive dryness, hairiness from a dry constitution.

The cause of prolonged wakefulness is a dry brain, continual thought, discontent, fears and cares that give the mind no rest. Sexual incontinence comes from wind and a hot liver: Montanus, consultation 26. Rumbling in the bowels is caused by wind, and wind by poor digestion, weakness of natural heat, or disordered heat and cold. Palpitation of the heart comes from vapours, and heaviness and aching from the same cause. Wind causes the hardness of the belly and the jumping sensations in various parts. Redness of the face and itching, as though bitten by fleas or stung by ants, come from a sharp, subtle wind. Cold sweat comes from vapours rising from the hypochondria and settling on the skin; leanness, from lack of good nourishment.

Why their appetite is so great, Aetius answers: “The mouth of the stomach grows cold.” Cold in those internal parts, a cold belly and hot liver, causes indigestion; and tension proceeds from disturbances. Our soul, lacking spirits, cannot attend precisely to so many operations requiring concentration. Exhausted and overmastered by passion, she cannot consider the reasons that might dissuade her from such affections.

Bashfulness and blushing are a passion peculiar to human beings. They are not caused only by shame and disgrace, or by consciousness of some foul deed committed, but, as Fracastorius determines, “because of one’s own deficiency and fear”: from fear and an awareness of our defects. The face struggles and is troubled in the presence of someone who sees our defects; nature, seeking to help, sends heat there; heat draws the finest blood, and so we blush. The bold, arrogant and careless seldom or never blush; the fearful do.