Letting go of irrational beliefs
Being able to change your beliefs is necessary for keeping on playing a positive role in the world. Not being able to think critically about your own beliefs and to change them when they are not true eventually will keep you from playing a constructive role. An ultimate example of the inability to change one's views can be found in religious fanatics who create death and destruction while believing they are doing something good. Letting go of beliefs can be important but also hard.