Consistency requires you to be as ignorant today as you were a year ago.
Nancy Segal, a New York City resident, bought a ticket to the ballet. An hour before she was to leave for the performance, she felt tired and a bit sick. She didn’t feel like walking eight blocks to Lincoln Center or sitting for three hours. What she really wanted to do was put her feet up on the couch and spend the evening reading a book, but she forced herself to go to the ballet. Her explanation? “I spent $120 for that ticket, and I wasn’t about to waste my money.”
Nancy made an irrational decision. She was taken in by the concept of sunk costs. If Nancy had been rational, she would have based her ...