John Maynard Keynes was twitted with changing his mind. He replied, "When the facts change, I change my opinion. What do you do, sir?"
My favorite example of a change of mind was Norman Mailer at The Village Voice.
Norman took on the role of drama critic, weighing in on the New York premiere of Waiting for Godot.
Twentieth century's greatest play. Without bothering to go, Mailer called it a piece of garbage.
When he did get around to seeing it, he realized his mistake. He was no longer a Voice columnist, however, so he bought a page in the paper and wrote a retraction, praising the play as the masterpiece it is.
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[T]he Constitution, rather than suggesting that all behave in a godlike manner, recognizes that, to the contrary, people are swine and will take any opportunity to subvert any agreement in order to pursue what they consider to be their proper interests.
To that end, the Constitution separates the power of the state into those three branches which are for most of us (I include myself) the only thing we remember from 12 years of schooling.
The Constitution, written by men with some experience of actual government, assumes that the chief executive will work to be king, the Parliament will scheme to sell off the silverware, and the judiciary will consider itself Olympian and do everything it can to much improve (destroy) the work of the other two branches. So the Constitution pits them against each other, in the attempt not to achieve stasis, but rather to allow for the constant corrections necessary to prevent one branch from getting too much power for too long.
Rather brilliant. In the abstract, we may envision an Olympian perfection of perfect beings in Washington doing the business of their employers, The People, but any of us who has ever been at a zoning meeting with our property at stake is aware of the urge to cut through all the pernicious

and go straight to firearms.
I found not only that I didn't trust the current government (that, to me, was no surprise), but that an impartial review revealed that the faults of this president—whom I, a good liberal, considered a monster—were little different from those of a president whom I revered.
Bush got us into Iraq, JFK into Vietnam. Bush stole the election in Florida; Kennedy stole his in Chicago. Bush outed a CIA agent; Kennedy left hundreds of them to die in the surf at the Bay of Pigs. Bush lied about his military service; Kennedy accepted a Pulitzer Prize for a book written by Ted Sorenson. Bush was in bed with the Saudis, Kennedy with the Mafia. Oh.
And I began to question my hatred for "the Corporations"—the hatred of which, I found, was but the flip side of my hunger for those goods and services they provide and without which we could not live.
And I began to question my distrust of the "Bad, Bad Military" of my youth, which, I saw, was then and is now made up of those men and women who actually risk their lives to protect the rest of us from a very hostile world. Is the military always right? No. Neither is government, nor are the corporations—they are just different signposts for the particular amalgamation of our country into separate working groups, if you will. Are these groups infallible, free from the possibility of mismanagement, corruption, or crime? No, and neither are you or I. So, taking the tragic view, the question was not "Is everything perfect?" but "How could it be better, at what cost, and according to whose definition?" Put into which form, things appeared to me to be unfolding pretty well.
Do I speak as a member of the "privileged class"? If you will—but classes in the United States are mobile, not static, which is the Marxist view. That is: Immigrants came and continue to come here penniless and can (and do) become rich; the nerd makes a trillion dollars; the single mother, penniless and ignorant of English, sends her two sons to college (my grandmother). On the other hand, the rich and the children of the rich can go belly-up; the hegemony of the railroads is appropriated by the airlines, that of the networks by the Internet; and the individual may and probably will change status more than once within his lifetime.