One of my favorite psychological effects is the Rosenthal effect. It is that the quality of our expectations affects the outcome of our actions.

Here is a simple example. In 1963, psychologist Robert Rosenthal proposed to his students to teach rats to go through labyrinths. He told half of the students that their rats were geniuses, the other half that their rats were stupid. Those who trained “capable” rats achieved better results than students who trained “stupid” rats. There was no difference between the rats.

This experiment has been repeated many times in different contexts. For example, teachers were given different classes and they were told that some were smart students, while others were not very smart. In fact, there was no difference between the students, but it was not difficult to guess which teachers they achieved the greatest success.

If I tell you, “Believe that you will succeed,” it will sound like the banal advice of a success guru. But I’m still convinced of the Rosenthal effect, so I’ll say differently.

If you do not have a drop of faith in what you will succeed, should you be surprised that in the end nothing has succeeded?