When you can keep your attitude in the state of not happy and yet not unhappy, that means the selfish ideas and personal considerations can no longer affect the state of your attitude, and your attitude can take any challenges at ease under any kinds of pressure unaffectedly, reaching the true happiness. At the beginning, your attitude can easily be affected by worries and delusion, yet with the guidance of your concept, you are able to take the pressure at ease without being affected. The interaction between your attitude and concept helps you reach the true happiness. Therefore, to control and reinforce your attitude, you must allow your attitude to go through the challenge from any sources of pressure, and keep your attitude between the states of not happy and yet not unhappy.