We want the facts to fit the preconceptions. When they don't, it is easier to ignore the facts than to change the preconceptions.
Five senses; an incurably abstract intellect; a haphazardly selective memory; a set of preconceptions and assumptions so numerous that I can never examine more than minority of them - never become conscious of them all. How much of total reality can such an apparatus let through? - C. S. Lewis
Comedy should provoke! It should blast through prejudices, challenge preconceptions; comedy should always leave you different than when it found you. - Duckman (Jason Alexander)
The way to find out about our place in the universe is by examining the universe and by examining ourselves - without preconceptions, with as unbiased a mind as we can muster. - Carl Sagan