Not every belief that everyone has is true. If you are a person who is concerned with knowing what the truth is at some point you will ask others and ask yourself how you "know" what you know.
The scientific method is the best, if not the only method that humanity has come up with for discerning, reliably, what the truth is.
It may not tell you what you want to hear, but if you use it without cutting corners it will tell you the truth:
Introduction to the Scientific Method