John Maynard Keynes is frequently credited with the aphorism “When I find I’m wrong, I change my mind. What do you do?” Today, the problem may less be an attitude of stubbornness than that fewer people than ever recognize their mistakes in the first place.

In a well-documented fashion, steady doses of viewpoint reinforcement lead not only to a resistance to alternative positions but also to a more entrenched and passionate way in which thoughts are held and expressed. When those expressions are launched in the impersonal or even anonymous channels of today’s social — or is it antisocial? — media, vitriol often becomes the currency of discourse and second thoughts a form of tribal desertion or defeat. Things people would not say face to face are all too easy to post in bouts of blogger or tweeter one-upmanship.

So honest admissions of error are more eye-catching these days. In recent years, The Post’s Bob Woodward has recounted how, a quarter-century later, he had come to a very different interpretation of Gerald Ford’s pardon of Richard Nixon. And how he wasn’t the only one; Sen. Ted Kennedy, who excoriated Ford at the time of his decision, joined Woodward in that assessment, and conferred an award for political courage for the act they had once deemed a corrupt bargain.