GIGO, garbage-in, garbage-out, is a common phrase in the information technology fields.  What this means is that if the information you put into a computer is false, misleading, or incomplete, than the conclusions calculated by the computer will also be false or misleading.  The same is true for the information we put into our brains.  If we fill them with information that is widely accepted, but false, the brain will come to false conclusions.  Also the subconscious filters will filter based on that information so you accept more information that backs up the false beliefs while ignoring information that conflicts with it.  The result is that we than end up with an endless cycle of
GIMGI, garbage in, more garbage in, until our minds are full of false or misleading data while much of the true information has been blocked.
    This can be corrected by questioning all so-called facts, even those you have believed forever, and when someone tells you something, don't just accept that it is true, look for proof and also look for evidence that it isn't true before you accept it.  You can also awaken your soul which is not as easily fooled as your mind is.