It kind of goes along with what J.K. Rowling said, but I’ll say it anyways:
It is impossible to be right about everything. At some point in the future something you believe to be true will be shown to be false. That thing may be very important to you, but that does not change the truth of it. Be prepared to accept these moments when you will be wrong and learn to face them with dignity. An opportunity to learn is more important than stubborn pride and a belief in one’s own perfection.