“The fact that someone says something doesn’t mean it’s true. Doesn’t mean they’re lying, but it doesn’t mean it’s true.
All of us cherish our beliefs. They are, to a degree, self-defining. When someone comes along who challenges our belief system as insufficiently well-based – or who, like Socrates, merely asks embarrassing questions that we haven’t thought of, or demonstrates that we’ve swept key underlying assumptions under the rug – it becomes much more than a search for knowledge. It feels like a personal assault.
In his celebrated book, ‘On Liberty’, the English philosopher John Stuart Mill argued that silencing an opinion is “a peculiar evil.” If the opinion is right, we are robbed of the “opportunity of exchanging error for truth”; and if it’s wrong, we are deprived of a deeper understanding of the truth in its “collision with error.” If we know only our own side of the argument, we hardly know even that: it becomes stale, soon learned by rote, untested, a pallid and lifeless truth.
The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we desperately want to be true. But our preferences do not determine what’s true.
It seems to me what is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas. If you are only skeptical, then no new ideas make it through to you. On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish the useful ideas from the worthless ones.”
– Carl Sagan