11 The Reckoning of the Time The keys to the calendar So Gregory summoned one of his advisors, a German priest named Christopher Clavius (Christoph Klau), called the “Euclid of the 16th century.” Clavius was that sort of Renaissance man who was really most prominent in the Middle Ages: born and raised in Bavaria, professor in Portugal, and papal mathematician and astronomer in Rome. Tycho Brahe and Johannes Kepler esteemed him highly, and he was a lifelong friend of Galileo. His voluminous works were translated into various languages; these included Chinese, so that his fellow Jesuits, such as his student Matteo Ricci, the great missionary to China, could take them to that land of clockmakers and stargazers and seekers of the Order of Heaven. The most obvious need was to get rid of the ten “extra” days that had intruded. But Gregory and Clavius wanted more than calendrical duct tape. They wanted a solution that would, for all practical purposes, settle matters once and for all. That required excruciatingly precise astronomical observation and measurement and computation. What Clavius came up with was perfect, and was implemented in Catholic nations by papal decree in 1582. That year, if your birthday fell between October 5 and 14 inclusive, well, you might as well
RkJQdWJsaXNoZXIy NzMzNzY=