#17 Ian

Having only a sketchy knowledge of what a palimpsest is, I wikied it and found the following:

..the consumption of old codices for the sake of the material was so great that a synodal decree of the year 691 forbade the destruction of manuscripts of the Scriptures or the church fathers, except for imperfect or injured volumes. Such a decree put added pressure on retrieving the vellum on which secular manuscripts were written.

It's hard to imagine a time when writing materials were so expensive that people would go to such lengths to clean off and reuse them.

Religion does poison everything.

Well...Jews in the Middle Ages, and sometimes even today, avoided destroying or reusing any piece of writing with the name of God on it (hence why some write God as G-d) and would instead put them away in a geniza, a storeroom, in the synagogue. A chance discovery of such a room in Cairo, the Cairo Geniza, has been one of the most important sources of first-hand documentation of Middle Eastern medieval history, with 200,000 manuscripts dating from medieval times to the 19th century. Had the original owners of these manuscripts not had such an irrational belief, we would be the poorer for not having them. (Then again, I suppose it could be said that life was made much poorer for countless numbers of people because of silly religious rules like that one...)