most people don't realize they are a three-part being

body, mind, soul

the ego (mind) is born here, and is survival machine. one strategy is join with strong opinions, go with the masses...

these are the people that pick a side based upon apparent strength

when confronted with Truth that makes their side weaker they have no idea how react. they didn't actually know why their believe (just as you said)

all they know is 'many others believe, and strength in numbers must be right'

mark twain was of the opinion the exact opposite is true.. if the masses believe it.. that is the lie