I apologize in advance if I come across as a party pooper—that person at magic shows who ruins the fun for everyone by giving away the magician's secrets, but there is no magic involved in what is usually referred to as "group levitation." Levitation, spoon-bending, and the Ouija board are all based on similar, completely natural, psychological and physiological phenomena.
There are a few scientific principles at work here. Group levitation usually begins with a person telling the other participants how "impossible" it is to lift someone with just the fingers. This statement sets the expectations of the participants as to how they are expected to perform in the levitation game. It also activates a form of the placebo effect where belief alters the person's subjective experience. Now, the first attempt to lift the person is made, before the magic chants or rituals take place, and the participants conform to their expected roles, and find it very difficult or "impossible" to lift the person. Since most people are susceptible to the power of suggestion, the one or two skeptics in the group who do exert the full force initially will find that their efforts were not enough to "levitate" the person, given the lack of force exerted by all the other participants. Next, the magic chant or ritual is explained, and the new expectation of success is set. But this new expectation and the power of suggestion only play a role in the illusion of levitation. As one enters a meditative state by chanting, prayer, or reciting "spells," or if one experiences a rush of adrenaline, the focus is taken off the physical aspects of the task. Consciously, we do not feel as if we are applying sufficient or even controlled force to accomplish the task (i.e., lifting a person, bending a spoon, directing a device to a certain letter, etc.) but physically, we are. This is known as the ideomotor effect. The illusion is an impressive one, but the reality of the situation often gets lost with years of retelling the story due to memory biases. Like the 6-inch fish that became the 16-inch fish, yesterday's impressive illusion is remembered today as a supernatural event.
I have experienced and participated in some of these events (I wrote about one such experience in detail in one of my books). I participated as an objective participant—and I did this all as an adult, within the last ten years. It was certainly "neat," but no more so than any card trick, and there is no superhuman strength involved. Let's do the math. The average weight of a 13-year-old boy is about 100lbs. Assuming six people are doing the "levitating," that is about 16lbs per person, or 8lbs per hand—the weight of a big book—*if* you were lifting your fair share. Think about it—if magic were happening, why would it be necessary to even use hands to begin with? Why do you think this "magic" has never been demonstrated under controlled circumstances? It would be fairly easy to set up pressure sensors on each contact point. If the sum of the pressure applied is less than the weight of the person, something strange indeed is going on. An easier (but less accurate) way is to have all the participants stand on scales and record and add all the readings when the body is lifted, but not being raised or lowered. As far as I know, no scientist has as ever bothered to test this in a controlled environment for the same reason researchers aren't scientifically baffled when magicians pull coins out of someone's ear. Group levitation is is a very common party trick with many strong naturalistic explanations.
It is common for people to think that what needs explaining is the defiance of gravity when it fact, it is the reason why people think gravity has been defied that needs explaining. Objectively, nobody defies gravity in the group levitation trick. Favoring a natural explanation over a magical one may defy "common sense" since common sense is based what we do perceive not what we don't, but with the help of psychology we can identify yet another time when science demonstrates that our common sense is wrong. Group levitation is not a question of physics; it is a question of the human mind and perception. A question that has been answered.
Reason: Book I - A Critical Thinking-, Reason-, and Science-based Approach to Issues That Matter is based on the first two years of The Dr. Bo Show, where Bo takes a critical thinking-, reason-, and science-based approach to issues that matter with the goal of educating and entertaining. Every chapter in the book explores a different aspect of reason by using a real-world issue or example.
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