A hundred years ago it used to be said with pride that if you gave a zoologist a single bone he could reconstruct the entire animal for you. We know that such reconstruction worked much harm to science. Many of the animals possess structures that even important portions of their anatomy in other parts of the body would give no hint of. History that is built up from single incidents is likely to be even more false because human conduct is much more complex than any animal body. What could be expected of the zoologist’s reconstruction, however, if the original bone handed to him was factitious, what a curious result might be expected from his deduced skeleton.
This is what happened with Professor Draper’s reconstruction of history from certain incidents that he accepted. The story of the Papal Bull against Halley’s comet seemed enough to him to make it quite clear that for centuries the Popes must have been buried in the profoundest ignorance of science,–but then the story of the Papal Bull against Halley’s comet is all a modern invention. Draper said: “But when Halley’s comet came in 1456 so tremendous was its apparition that it was necessary for the Pope himself to interfere. He exorcised and expelled it from the skies. It slunk away into the abysses of space terror-stricken by the maledictions of Calixtus III, and did not venture back again for seventy-five years!” Of course this bit of supposed information is all nonsense; Calixtus did no such thing, and just at that time the Popes were encouraging Cardinal Nicholas of Cusa in his great mathematical work and astronomical speculations, were inviting Regiomontanus, “the Father of modern astronomy,” down to Rome to do his work there and help in the correction of the calendar, while Cardinal Bessarion, one of the most intimate friends of the Pope at this time, was encouraging Purbach at Vienna and Regiomontanus to translate Ptolemy and providing them with manuscripts and putting them in touch with Greek science in every way.
James J. Walsh, The Popes and Science (1908)