If we’re to publish, teach, invent, imagine or promote, we need the confidence to believe that we have something to offer. That we are, in some way, right.
But the enterprise of rational thought is based on theories, tests and improvements. We can never be certain, all we have is the best available explanation.
So the hard work is to speak up at the very same time you’re open (in fact, eager) to change your mind based on new data.
One without the other is worthless.