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No. 1406:
Medieval Age of Reason

Today, a brief bright era in medieval Europe. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

In AD 1277, the Bishop of Paris issued a condemnation listing the 219 "execrable errors" students were being taught at the University of Paris -- the intellectual center of the world in those days. For two centuries, Europe had been open and freewheeling. A technology of water wheels, windmills, cathedrals, and manuscript book production had leapt forward. Universities had grown up.

Historian Jean Gimpel says the Bishop's edict was the beginning of the end of that glorious age. The Church had led intellectual and technological change for a long time. Now a chill passed over the land. Philosophy and religion began taking separate paths. No great movement ever reaches an enduring equilibrium, and medieval advances needed time to settle in before they could emerge in different forms and different places. But, for now, Europe had come halfway from a wilderness to modern times.

In 1085 Spain's Islamic City of Toledo had fallen to Christians who'd occupied it without a fight. Western Christianity suddenly had access to the vast library of classical books preserved in Toledo by Islamic and Jewish scholars. It was a literature they'd known only as vague echoes of a vanished past up to then.

Christian scholars were astonished to see that one of those ancients, Aristotle, offered a whole philosophical system. Aristotle's system brought two powerful elements to the table: his method of using logic, and a science based on observation. Pierre Abelard, who was only six when Christians got into the Toledo Library, became first in a line of scholars who set about rebuilding education so as to combine Aristotle with Christianity.

But when the acquisition of knowledge rests on detached logic and observation, you have little latitude for deciding outcomes ahead of time. That inevitably removed any guarantee that scholars would continue to support specific interpretations of scripture.

It'd be centuries before Aristotle's observational science evolved into modern scientific method. His mathematical logic was another matter. For people like Robert Grosseteste and his student Roger Bacon math was a new toy. They used geometry to correct ideas about optics. Bacon not only set the stage for the invention of eyeglasses, he also used math to reform the Christian calendar.

Church fathers weren't concerned at first. They didn't see how this was chipping away at Church teachings. Rumblings of worried clerics weren't heard 'til the mid-1200s. Then that Bishop's edict! It was damaging, all right, but the genie was out of the bottle.

Abelard named that genie when he said, "By doubting we are led to questions, by questioning we arrive at truth." Of course that eventually brought reactionaries out of the woodwork. It always does. Abelard had clearly seen that honest doubt is the rock upon which every revolution in human thinking inevitably sits.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)

Gimpel, J., The Medieval Machine: The Industrial Revolution of the Middle Ages. New York: Penquin books, 1976. (See especially, Chapters 8 and 9.)


Image of Mercury and the Artisans