Dear Dan,

Thanksgiving is around the corner, including Black Friday, the largest shopping day of the year, when many people spend way too much money. How do we stop this insanity?

—John

People do spend a lot of money on Black Friday, but is that really so irrational? To figure that out, we need to ask which state of the world we should compare this tradition to. If you assume that we could get people to blow less money on Black Friday and decrease overall irresponsible spending, then of course the world would be a better place without Black Friday.

But what if canceling Black Friday just spurred people to start living beyond their means every month of the year? And what if this extra increase in monthly splurging turned out to be larger than the spending increase on Black Friday itself? If all this were true, we would be better off with Black Friday.

Let’s think about dieting as an analogy for shopping. Many diets allow for a “cheat day” because they realize that without the permission to indulge sometimes, people are likely to give up dieting altogether. So the people who design diets have figured out that allowing people to go wild from time to time helps them behave well most of the time. What if Black Friday is the shopping equivalent of the cheat day?

I don’t endorse wasting money, but perhaps we should all figure out how much money we are willing to splurge with, take it in cash and indulge—but only at decent intervals.