Well i believe chackra's are the best examples about the placebo effect. Concentrate on any part of your body and believe that a chackra exists there. Close your eyes and wait.

This is nothing but fooling your mind!

But if it works, it works.

Anyway our subconcious mind fools us when we are dreaming. We realize we are dreaming by seeing something stupid. And realizing we are in a dream. So why not fool the subconcious or concious mind with chackras?
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