A certain department store sends me coupons all the time in the mail–either 15, 20, or 30%. It’s rare that one isn’t lying on my counter. The trouble is, I rarely remember to take it with me when I shop. I’m such a spur-of-the-moment person that I often just pop in on my way to or from somewhere else.

The store has a pretty liberal policy about those things. Whenever I’m checking out, the cashier will ask if I have a coupon. Invariably, I’ll have to respond that I’ve left it at home. No problem, says the cashier. What was the discount on it?

Herein lies the dilemma.

Call it upbringing, but I always answer truthfully. I think it was 15%, I’ll say. Nonplussed, the cashier will gently prod me, Are you sure? After answering in the affirmative, I’ll belatedly realize that the cashier is giving me the opportunity to increase my savings, thinking I’ll correct myself and go for the 30% discount rather.

For some reason, I just can’t do it.

Besides the fact that it never occurs to me until the opportunity has passed, the knot in my chest that grows when I’m not completely truthful won’t let the words clear my voice box.

Often I think this is just another of my strange quirks, but sometimes I wonder if it’s more than that. I hate, hate, HATE to be on the receiving end of a lie, and let’s just say that my upbringing reinforced the value of not being on the giving end, too. I have a deeply ingrained habit of needing to believe the stories I tell are true. When they’re not, I can’t get the words out.

I know (and love) lots of people who would go for the big discount–and I don’t blame them. But if paying a little more is the result of a deep-seated behavior that serves me well in so many other areas, take my money. If I start turning it off, a day might come when I forget to turn it back on.