Are you asking what the rest of us believe or do you want a reason for not having to believe what others believe?
In any case, all the knowledge and information we have at our disposal is the accumulated wisdom and thinking of religious, historical, scientific and philosophical scholars of the past and present.
Some of it is provable, some self-evident and some of it speculative. If you want to decide what makes sense and what doesn't, you should study the works of the greatest scientists, thinkers and historians and then choose what you want to believe.
We are rational beings who have the freedom to think and believe what we want and our best bet is to make it as informed and knowledgeable as possible.