That quote has been my personal mantra for as long as I can remember.
I remember stumbling upon that quote in a novel that I've been reading in elementary. With a bit of research, I understood the meaning behind those words and decided to absorb it in my life. It teaches me to accept life as it is, as we are but riding a wave of uncertainness in a sea of life.
It has been my blanket response for every discomfort that I felt towards living in general.
As it turns out, by making this your personal mantra, you are preparing yourself to be disappointed over and over again, whether it be towards the things you can't control, people, family, and even yourself. You are preparing for failure even before you start the race.
That's why I am always surprised by every good thing that has happened in my life. Graduating college, getting our visas accepted, graduated [again] for a diploma course, and the list goes on.
