Then the researcher inserted a piece of glass into the second tank, creating two chambers. The barracuda again attacked, but this time he hit the glass and bounded off. He kept repeating this behavior every few minutes. Eventually the barracuda gave up.
The researcher repeated this test over several days, and each time the barracuda became less aggressive, until he eventually stopped striking altogether. Then the researcher removed the glass. The barracuda was free to swim where he wished. But now he was trained to believe there was a barrier between him and the fish and didn't attack.
How many barriers do we have that exist only in our mind; barriers that keep us from achieving our desired results?
(Hat tip to Michael Hyatt for the story of the barracuda.)