The intellectual milieu of Chaucer was ultimately controlled by a religious vision common to medieval culture. It is of course to be found in the Retraction at the end of The Canterbury Tales, where the poet prays that his sin of writing secular and courtly literature may be forgiven. Similarly, gentilesse or nobility and courtly love acquire a deep spiritual content. This is hardly surprising since the Christian church played a central role in the life of the people, and the parish priest, even more than the passing friar, was the chief instructor. Its dedication to Christ’s teachings led it or, at least, sections of the clergy to denounce the social evils of the day. The Lollards dominated the literature of satire and complaint. Followers of the heretical Wyclif, they were aided in their criticism by mystical writers like Dame Juliana of Norwich, Richard Rolle and the anonymous author of The Cloud of Unknowing. These mystics undermined institutional religion by their emphasis on a personal relationship with God. The Lollards are also remembered for the first English translation of the Bible under the guidance of Wyclif.
The cosmos of the Middle Ages was providentially ordered and harmonious. The earth was the point-sized center of a system of crystalline concentric spheres for the planets to go around. This Ptolemaic, geocentric model was displaced in the Renaissance by the Copernican heliocentric (sun at the center) universe. But in the Middle Ages it was held together by Gods’ love, which controlled all the cycles of seasons, tides, birth and death. According to medieval belief, the stars as agents of Destiny combined with Fortune as powerful influences on human life. Of course, God’s providence worked in everything, although men could not grasp its ways.
Astrology and medicine were closely related in Chaucer’s world. Each of the twelve signs of the zodiac was thought to control a different part of the human body; moreover, the physical characteristics and nature of each person were determined by his horoscope at birth. This gave rise to the four medieval ‘humors.’ Physicians treating a patient would first cast his horoscope; then combining this with the positions of the stars when the illness began and when the doctor paid his visit, they would attempt to heal.
Related to astrology was the pseudo-science of alchemy. Chaucer’s yeoman in The Canon’s Yeoman’s Tale knowledgeably refer6 to the four spirits and seven bodies. The spirits are quicksilver, arsenic, crystalline salt and brimstone and the bodies are the medieval planets (including the sun and the moon). Thus gold belongs to the sun, silver to the moon, iron to Mars, quicksilver to Mercury, lead to Saturn, tin to Jupiter and copper to Venus. Chaucer’s contemporary, John Gower, wrote nearly two hundred lines in the Confessio Amnntis on alchemy.
Chaucer’s doctor refers to many learned authorities on medicine. Among the classical sources are Hippocrates and Galen; among the Moslem physicians we find Avicenna and Averroes. Finally we have English physicians of the late thirteenth and early fourteenth centuries: Gilbertus, Anglicus, Bernard, Gaddesden. The human body was believed to have four fluids or ‘humors’ of which one would always predominate. If blood was predominant, we would have a ‘sanguine’ person; if phlegm, a ‘phlegmatic’ person, if choler, a choleric person and if black bile, a ‘melancholic’ person. Chaucer’s Reeve is choleric, Franklin melancholic. Humors determined temperament and physical make-up, and the latter was also shaped by the stars. According to Galen, the doctor had to consider the four elements of earth, water, air, fire and the four qualities of hot, cold, dry, and moist in treating the body. ‘Each of the twelve zodiac signs was related to the elements, qualities and humors. Not only are the human mind and body thus closely related but man himself is further related to the larger order in the universe.
Another medieval science in which Chaucer had an interest was the science of dreams. Here, his source, Macrobius’ commentary on The DI-earn of Scipio, lists five types of dream: the Somnium, the visio, the oraculum, the insomnium, the phantasma or visium. The somnium is a dream requiring symbolic interpretation by an expert. The visio reveals a coining event exactly as it will be. In the oraculum a spirit or relative or an important person appears to the dreamer and announces what is lo happen. By contrast to these prophetic dreams, the insomnium and the phantasma indicate nothing apart from the dreamer’s physical state. The former may be produced by fear or worry or digestive disturbances; the latter is a kind of delusion.