Thought I would add there have been many studies on prayer and medical outcomes. When the people didn't know people were praying for them there was no change in outcomes. When people did know they had slightly poorer outcomes than the control group. It was put forth that the act of people praying for them and them needing to get better to prove thier faith stressed them out. Prayer from all flavors of religion has been proven to have at best the same effect as a placebo to worse outcomes - it is a total waste of trying to help and failure on all levels.Ok, so I thought I would go back to the OP and discuss what people apparently think is a barbaric mistake.Anyway, to plus3, so I assume that you still believe in leeches curing most diseases right? Because at one point that was thought to be the case and at that time could be considered "science".
At the time of its use, medical science was not far at all; especially due to the high level of religious institutions that would still have enough influence to impact anyone who would seek information that may disprove a god.
There is no doubt that the idea that all illness resulted from an imbalance of the four humours (or some other such theory)—blood, black bile, yellow bile, and phlegm—is incorrect, but scientists of the time were still on the right track.
Bloodletting, or phlebotomy, through leeches actually helped with a few of the more common sicknesses such as heart disease, high blood pressure, and pulmonary oedema. Even a few rare diseases, such as haemochromatosis, where there is an overabundance of iron in the blood, required simple bloodletting and today it still remains as the most common solution.
The most important lesson to gain is that science put us on the right track as we continue to find patterns and modify our knowledge. I would say the possible chance that leeches could help is still better than the alternative, which would be to sit down and pray with a guaranteed effectiveness of zero. Well, perhaps .0001 as there are times when the placebo effect could allow a person to cure oneself.
There are major problems with disbelief in reality. There was a case of a woman whose newborn unfortunately happened to suffer brain injury and became essentially brain dead. Her religious leaders told her it was because of her sins an she needed to atone for them to save the child. So on top of the monumental pain of losing her child all that additional crap got piled on. Then the baby died. Good job helping people religion!