The top layer of writing in this 700-year-old book describes Christian prayers. But underneath, almost obliterated, are the only surviving copies of many of the works of the ancient Greek mathematician Archimedes.
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An intensive research effort over the last nine years has led to the decoding of much of the almost-obliterated Greek text. The results were more revolutionary than anyone had expected. The researchers have discovered that Archimedes was working out principles that, centuries later, would form the heart of calculus and that he had a more sophisticated understanding of the concept of infinity than anyone had realized.

Archimedes wrote his manuscript on a papyrus scroll 2,200 years ago. At an unknown later time, someone copied the text from papyrus to animal-skin parchment. Then, 700 years ago, a monk needed parchment for a new prayer book. He pulled the copy of Archimedes’ book off the shelf, cut the pages in half
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“The interesting breakthrough is that he is completely willing to operate with actual infinity,” Netz says, but he adds that “the argument is definitely not completely valid. He just had a strong intuition that it should work.” In this case, it did work, but it remained for Newton and Leibniz to figure out how to make the argument mathematically rigorous.