In Search of the Scientist Pope, Gerbert of Aurillac (ca. 950-1003)

In the Year of Our Lord 999 the archbishop of Ravenna sat down to answer a letter.

In nine months the world would end. There had come famines, floods, comets, eclipses, earthquakes, volcanic eruptions, wolves in churches, rains of blood—so many signs and wonders they could not be counted. Gog and Magog, in the form of Vikings, Magyars, Saracens, and Huns, besieged Christendom on all sides. Tears flowed from a holy cross. The Virgin Mary appeared in a stone. The cathedrals at Orleans and Mont Saint-Michel were destroyed by fire. It was the darkest year of the Dark Ages.

Or was it? The End of the World was not oppressing this archbishop's mind. A copy of his letter still exists. I read it in a modern translation made by Harriet Pratt Lattin in 1961. "Gerbert greets his still beloved and ever to be cherished Adalbold with honest fidelity and unchanging sincerity," he wrote:

You have requested that if I have any geometrical figures of which you have not heard, I should send them to you, and I would, indeed, but I am so oppressed by the scarcity of time and by the immediateness of secular affairs that I am scarcely able to write anything to you. However, lest I continue mentally disobedient, let me write to you what error respecting the mother of all figures has possessed me until now.

In these geometrical figures which you have already received from us, there was a certain equilateral triangle, whose side was 30 feet, height 26, and according to the product of the side and the height the area is 390. If, according to the arithmetical rule, you measure this same triangle without consideration of the height, namely, so that one side is multiplied by the other and the number of one side is added to this multiplication, and from this sum one-half is taken, the area will be 465.… Thus, in a triangle of one size only, there are different areas, a thing which is impossible …¹

A 19th-century rendition of Sylvester II. From E. Mennechet, ed., Le Plutarque Français, Vies des Hommes et Femmes Illustres de la France … Volume 1 (Paris, 1835).

I was astonished: on the eve of the Apocalypse the archbishop and his friend (soon to be bishop of Utrecht) are discussing the best method for finding the area of a triangle.

It is the last letter we have from Gerbert of Aurillac before he became pope in April 999 under the name Sylvester II. Before the pope's death in 1003, Adalbold would pester the busy man again, this time concerning the volume of a sphere.

For Sylvester II was "The Scientist Pope." To tell the story of his life, I discovered, meant rewriting the popular history of the Dark Ages. The Earth wasn't flat. People weren't terrified that the world would end at the stroke of midnight on December 31, 999. Christians did not fear Muslims and Jews. The church wasn't anti-science—just the reverse. Mathematics was among the highest forms of worship, for God created the world, as scripture said, according to number, measure, and weight. To study math was to approach the mind of God.

Gerbert of Aurillac left us over 200 letters and a handful of scientific treatises. He is mentioned in the letters or chronicles of several men who met him or lived during his lifetime. They make it clear that he rose to the highest office in the Christian church "on account of his scientific knowledge"—not in spite of it. They call him a man of "great genius and admirable eloquence," possessing "incomparable scientific knowledge." He "surpassed his contemporaries in his knowledge," was "acutely intelligent," and "deeply learned in the study of the liberal arts."²

Born a peasant in the mountainous Cantal region of France in the mid-900s, Gerbert entered the monastery of Saint-Gerald's of Aurillac as a child. There he learned to read and write in Latin. He studied Cicero, Virgil, and...