" Put together two stock market forecasts - one predicting that prices will rise next month and one warning of a drop.
Send the first mail to fifty thousand people and the second mail to a different set of fifty thousand.
Suppose that after one month, the indices have fallen. Now you can send another mail, but this time only to the fifty thousand who received the correct prediction.
This fifty thousand you divide into two groups: the first half learns prices will increase next month, and the second half discovers they will fall.
Continue doing this. After ten months, around a hundred people will remain, all of whom you have advised impeccably.
From their perspective, you are a genius. You have proven that you are truly in possession of prophetic powers.
Some of these people will trust you with their money.
Take it and start a new life in Brazil. "

― Rolf Dobelli , The Art of Thinking Clearly