Inception

Once a negative thought enters your mind, you have to be a wise of it and endeavor to replace it with a constructive one. The negative thought will try again to enter your mind, and then you have to replace it again with a positive one. It is as if other are two pictures in front of you, and you choose to look at of them and disregard the other. Persistence will eventually teach your mind to think positively and ignore negative thoughts.