To be right you have to be wrong?

After watching a number of videos of Milton Friedman and some other great public figures, I realized that they usually take a posture and defend it... even if it means to say something completely stupid. When I relate that to my own experience, I realize that yes indeed many times I have defended my posture by making use of resources that mislead. I guess the important thing to do is to acknowledge our misdeeds and apologize to whomever we offended, or just to admit being wrong. I guess it is better to say sorry than building up lies.