Never Give in!... Never Never Never!
You must 100% understand and envision what your purpose is in this mission. This is your personal journey of self discovery. You must understand what your reason for fighting is and it must be clear as day. If you don't know then you have already sabotaged yourself and if you cant answer this simple question without being cliche then you are just a follower. Your purpose is by design and crafted for you and you alone. It is your destiny to fulfill your purpose and in doing so you must complete the mission. You must finish.
So you see. It is never about a need for selfishness because your purpose must extend beyond you. You must never give in to any path that does not complete this mission. It is simple. Everything standing between you and your purpose is inconsequential. Your mission is to finish. So you must never give in.
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Chung-fẽng also said, “Make no provision for retreat.” This means to have a mind that will not be altered. Its means that a man should be mindful that, although he advance well once or twice, he should not retreat when tired or in unusual circumstances. – Takuan Sōhō