With so many philosophies, doctrines, and teachings these days, it's hard to know what to believe. Here is a rule of thumb to help you decide.
"Do not believe in anything simply because you have heard it. Do not believe in anything simply because it is spoken and rumored by many, or merely on the authorty of your teachers and elders. But after observation and analysis, when you find that anything agrees with reason, then accept it and live up to it."
~ Buddha (c. 563 B.C.E–C. 483 B.C.E)