The placebo affect is a valid claim, but shamanism is a practice quite easy to confirm as real or fake. Religions, though, merely require a person to have faith. However, for the sake of arguing in order to extract such a claim, one must at least attempt to clarify the position one stands.
Religions are modern man’s attempt to explain one piece of shamanism: social and personal behavior according to the “chi”. Man’s selfishness for power, money and status has contaminated many religions altering its original truth. Some religions remain closer to the truth but words have been substituted either due to different languages or to disassociate themselves from shamanism.
To understand this partition, shamanism in the dawn of time was the practice of seeking energy, chi, the void, 6th sense, God, psychic, ghosts, deities, energy healing, herbs, power plants, astro bodies, dreaming, black magic etc. One simple term, Shamanism was the science of energy seeking. Shamanism is like the physical Earth and religions are like countries. Each religion and culture has a piece of the truth. Separate, they do not make up the truth but together they make up the Earth. Of course, the issue is that many truths have been distorted, and religions are emotional affairs.
The downfall:
Men back then did not have as much the intellectual understanding of physical/material world around them. Many associated natural phenomenon with unnatural occurrences.
Because of selfishness, men began to seek energy for their own benefits and many shamanistic practices became awfully macabre. For example, many sought eternity on Earth by switching consciousness into trees, rocks etc. In the height of Shamanism, knowledge was tremendous and acute. Many legends and myths we now considered were a reality, flying men, talking trees, men turning into tigers or animals, being two places at one time etc.
Many of these legends are found in most cultures. As these things were going on, also was selfishness for power, men eating men alive to absorb their power, total control etc.
Shamans did not look for the behavioral portion of shamanism. Only a handful understood that in order to control energy power, selfishness or ego must be obliterated from a person. In time, most shamans were destroyed but the science of shamanism survived.
Having seen what shamans of ancient time have done, many labeled such practices as evil. Most knowledge was lost and only older cultures still practice the bit of if that was left. Still, they tailored that power to their personal needs, languages and cultures.
Out of Shamanism were born religions focusing of social/personal behavior in order to reach “God”, banning or labeling the practice of power as evil and primitive. While this new focus is correct, it is only one tiny section of the truth.