Fear is not real.

One of the most important lessons is how fear is seen in this saga: not as a weakness, but as an enemy that you can face. To overcome fear, the Bene Gesserit, a political and mystic group, created the litany against it:

"I must not fear....

Fear only exists to you in your mind and it is protecting you from the unknown. 

As human being, it's going to be normal to feel fear. It's going to happen for the rest of your life, but you do now want to let your fear control you. That is the choice that you get to make. ...

It's a very real but often misunderstood struggle. The key thing to realize is that, in most cases, the fear is about the consequences of success, not the success itself. 

This fear likely has very strong and very old origins in a person’s past.