The ancient convention, both classical and biblical, had surfaced in the emotions of the medieval poet of Alain de Lille's De planctu naturae, who suffered "from laughter to tears, from joy to grief, from merriment to lament, from jests to wailing."(13) Laura's "sweet clement laughter" is introduced in deliberate contrast to the bitter tears streaming down the poet's face.(14) Beyond tears, Laura's sweet laughter could emit deadly darts and one could die laughing.(15) Cruelly the woman laughs at his weeping.(16) She is a woman of alternating moods, "pensiveness and silence, laughter and gaiety."(17)
The medieval iconography of laughter had been frankly ugly.
As that poet warned women, "If you have a tooth that is black or too large or growing out of place, laughing will cost you dear." He prescribed the decorum of ladylike laughter. "Let the mouth be but moderately opened, let the dimples on either side be small, and let the bottom of the lip cover the top of the teeth."(27) In the medieval canon yellowed or pointy teeth were ugly.(28) Jean de Meun's Roman de la rose taught that laughter should be so discreet as to reveal only pretty dimples.
Another peril of laughter was that its respiration propelled air more so than ordinary speech - and that air could be foul: bad breath.
Laughter not only bared the teeth but also distorted the face.
Ficino was influenced by the novel inclusion of laughter in the medieval canon of beauty but he elevated its ornament to philosophy.
Laughter had been very rare in, even absent from, serious medieval genres.
"Her modest lips dwell closely together and are not frequently parted for idle words." Nor did the virtuous Marcia even smile for Venus.(48) Yet its poetics, in the delicate example of beauteous Helen, and the poetry of Dante and Petrarch afforded beautiful women both gravity and laughter. Ficino incorporated that beauty to the philosopher in his letter to his friends by borrowing the strains of laughter as permissible and positive from the descriptions of beautiful women on whose lips it had been "sweet." His new modifier - gracious - was bold, however.
Ficino was optimistic, witty, playful in philosophy,(51) with a comical disposition exhibited in his correspondence with his friends.(52) But Ficino's genius was not a liberality with laughter: he belonged to the moderates, who accepted laughter as a natural act but tempered its usage by propriety.
Yet Ficino invented another laughter, a laughter expressing the expansion of spirit, in distinction to the laughter resulting from the dilation of blood that was so worrisome for the health of intellectuals.
Composed in 1476,(60) it thus was a context or influence for his letter of circa 1480 commending gracious laughter. In an account of his theological opuscula he described the work as "Concerning Light, which in the divine powers is a rejoicing clarity and a clear joy, but in the fabric of the world is a kind of heavenly mirth arising from the delight of the gods."(61) Light had been an important Neoplatonist metaphor; Ficino elevated it to an imitation of God.(62) A chapter heading announced: "To the joy of the gods their heavenly eyes laugh and with a splendid motion they exult." Ficino traced the source of human sight to the supercelestial spirits, whose perfection of form, fecundity of life, perception of sense, certainty of intelligence, and "fullness of joy" was light.
The next chapter heading stated: "The laughter of the sky proceeding from the joy of the gods is light; it fosters and delights in everything." Ficino immediately joined human laughter to this divine laughter; extraordinarily, he made human laughter the analogy of divine laughter.
