The Tinkerbell Effect describes the situation where the more that people accept some proposition and act accordingly, the more true it becomes. A complementary "Reverse Tinkerbell Effect" occurs when a phenomenon becomes less true as more people believe in it.
The term was coined by Patrick Hynes in 2003, after Eugene Volokh put out a request for a name on his blog - the volokh conspiracy
Example
editAs an example, take the [Efficient-market hypothesis]], which states that all information relevant to determining the optimal price for a stock is incorporated withing the actual price. The more that people believe the EMH, the less likely these people are to trade stocks based on relevant news. But if nobody is trading based on relevant news, then any such news will never get incorporated into the shares price, and the EMH will thus be falsified.
Explanation
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