A Tale of Floss

There once was a couple who liked to floss and brush their teeth every night before bed. The husband flossed his teeth before brushing and the wife flossed after. Each of them had their opinion about which was more effective, and one day, they shared those opinions with each other.

Several months later, the couple noticed that they had both switched their flossing patterns. The husband now flossed after brushing and the wife flossed before. When they asked each other why, both of them admitted that the argument of the other had been so persuasive they had changed.