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"Your Highness, are you saying that blood is used to transport nutrients and oxygen?" Perna's large green eyes glittered, her pretty face full of earnestness, "So, if we let blood from a patient, wouldn't that make them even weaker?"
Joseph clapped his hands gently, "Indeed, you've uncovered the truth."
"Then why do we perform bloodletting as a treatment?"
"That is a mistake."
"No wonder you have always refused bloodletting treatments. Could all the doctors be wrong?" Perna nodded thoughtfully and then, suddenly looking at Joseph, hesitated a bit before saying, "Your Highness, what if... what if your conclusion is incorrect?"
"To study science is to have a spirit of doubt, to not blindly follow any authority." Joseph first nodded in approval of the female doctor, then continued, "Actually, it's quite simple to find out if something is right or wrong, we just need to do a double-blind experiment."
"Double-blind experiment? What is that?"