re: placebo effects, New Scientist had an interesting article on that and 12 other things that do not make sense. The placebo effect is actually weirder than I thought. In the article, there’s this experiment where you induce pain in someone several times a day, and manage the pain with morphine. On the last day, you use saline instead of morphine, which should have no effect, but it takes the pain away. Placebo effect.
The weird thing is, some guy changed the last step, adding a drug that blocks the effects of morphine to the saline. Shockingly, it no longer took the pain away. Meaning, it’s not just a mental; the saline placebo on the last day actually invokes the same physical reaction as the morphine does, and you can block a placebo effect. That’s weird.