Retarded Science

"It is remarked that no physician in Europe who had reached forty years of age ever, to the the end of his life, adopted Harvey's doctrine of the circulation of the blood; and that his practice in London diminished extremely from the reproach drawn upon him by that great and signal discovery. So slow is the progress of truth in every science, even when not opposed by factions or superstitious prejudices." -- David Hume, philosopher, History of England, 18th century