Why Encourage Dissent?

Why should we encourage dissent?  Because dissent potentiates a process that may lead us closer to the truth of things. Even when dissent is stupid and wrong-headed, it can make us think - assuming we're paying attention. 

Of course, there is a time and a place. We still have to make judgment calls on when we've heard enough and it's time to move on. But we also need to appreciate the depth of our ignorance and resist the tendency to dismiss challenges to our understanding of how the world works and should work.

Yeah, easier said than done. And the type of sentiment that just about everyone agrees with in principle yet violates all the time in practice, sometimes with good reason. But if being dismissive is our default response to challenge, we have a problem.

Change the default to a moment of openness and curiosity - Does that person have a useful or valid point? Is there something that I'm missing? And then see what happens.