Another example, from The Righteous Mind:

On February 3, 2007, shortly before lunch, I discovered that I was a chronic liar. I was at home, writing a review article on moral psychology, when my wife, Jayne, walked by my desk. In passing, she asked me not to leave dirty dishes on the counter where she prepared our baby’s food. Her request was polite but its tone added a postscript: “As I have asked you a hundred times before.”

My mouth started moving before hers had stopped. Words came out. Those words linked themselves up to say something about the baby having woken up at the same time that our elderly dog barked to ask for a walk and I’m sorry but I just put my breakfast dishes down wherever I could. In my family, caring for a hungry baby and an incontinent dog is a surefire excuse, so I was acquitted. [...]

So there I was at my desk, writing about how people automatically fabricate justifications of their gut feelings, when suddenly I realized that I had just done the same thing with my wife. I disliked being criticized, and I had felt a flash of negativity by the time Jayne had gotten to her third word (“Can you not …”). Even before I knew why she was criticizing me, I knew I disagreed with her (because intuitions come first). The instant I knew the content of the criticism (“… leave dirty dishes on the …”), my inner lawyer went to work searching for an excuse (strategic reasoning second). It’s true that I had eaten breakfast, given Max his first bottle, and let Andy out for his first walk, but these events had all happened at separate times. Only when my wife criticized me did I merge them into a composite image of a harried father with too few hands, and I created this fabrication by the time she had completed her onesentence criticism (“… counter where I make baby food?”). I then lied so quickly and convincingly that my wife and I both believed me.

I don't know whether Anna used this as an illustration, but one way by which I tend to notice myself rationalizing is when I'm debating something with somebody. If they successfully attack my position, I might suddenly realize that I'm starting to defend myself with arguments that even I consider bad or even outright fallacious, and that I've generally gone from trying to discover the truth to trying to defend my original position, no matter what its truth value.

Another example is that I might decide to do or believe something, feel reluctant to explain my reasons to others because they wouldn't hold up to outside scrutiny, and then realize that wait, if my reasons wouldn't hold up to outside scrutiny they shouldn't hold up to inside scrutiny either.

Do you experience either of those?