How we view the world—our worldview—is in the end the only thing that decides whether we suffer or find real happiness.
It's extremely important to realize that an entire civilization can be caught up for many years in a disastrously mistaken view of the world. For thousands of years sensible people believed that the world was flat. The courageous, democracy-minded founders of the United States kept human beings as slaves and believed they were animals, not people.
Our culture today has its own massively mistaken ideas of the world, and these cause all the hunger, poverty, sickness, and war in the world. If our peoples view of the world is causing pain to others and ourselves, then we must look for a better one, one that works. If it doesn't work, we cannot simply continue to follow whatever we learned as children, whether it came from parents or schools, churches or governments. True yoga is the search for a worldview that actually works to bring people happiness.
There are specific levels in our path where we eliminate, forever, different spiritual obstacles like doubt. We need to learn what these levels are, how to reach them, and how to stay there.