It Fell into My Mouth, Officer.

My name is Anne and I am have a problem.

It's a salty problem. A full-flavored, crunchy, calorie-dense problem. The problem comes in foil bags in multiple varieties, including a thick, ridged, hoity-toity variety flavored with garlic that, to my dismay, I am able to purchase at my local natural foods store with no licensure check, no drug test -in fact with no restrictions of any kind.

And Lo, at 4:00 PM today, it came to pass that I ate an entire bag of potato chips. It was not a small bag. Afterward I felt logy, dull, bloated with self-loathing. I cursed myself and my parentage. I scrapped the exciting plans I'd made for dinner: I was too full, and anyway I'd eaten two big-macs' worth of calories.

Why, oh WHY do I do this?! I told myself I'd only eat a couple of chips. I wasn't that hungry when I opened the bag, and dinner was just around the corner. After the first couple of chips, I told myself I'd only eat 17, the amount of 1 serving as articulated in the nutritional information. Then I granted myself a few more. And a few more. The next thing I knew there were only 17 chips left in the bag, plus a pile of crumbs, and I thought: What the hey?

The thing is, I am probably a more-than-typically conscientious person. I always consider the consequences of my actions; I always plan ahead; I exercise every day and make lists. So why did I eat the entire bag? Because I cower before the awesome power of the potato chip, for starters. But more importantly: Because I am human.

See, I've come to believe that a disproportionate number of our societal failures spring from the wrong-headed notion, hatched somewhere back in the Enlightenment, that humans behave rationally. Sometimes we do. Often we don't. Yet, for centuries, economic, social, and political policymakers have assumed we are rational units. This misapprehension has contributed to social dysfunction, the looming public-health and environmental crises, and even the recent economic downturn.

(People don't use 403bs because the plans are opt-in, not opt-out. People drive 10 miles for gas that is 10 cents cheaper. In their SUVs. And people will -oh yes they will- take out mortgages they cannot afford.)

Which is one of the reasons I'm so excited about the burgeoning field of behavioral economics. I haven't yet read Duke professor Dan Ariely's new book, Predictably Irrational: The Hidden Forces that Shape our Decisions, but I plan to. Publicized snippets of Ariely's research have already disabused us of the notion that bigger bonuses equal better performance, or that longer cash-in windows mean more people redeem gift cards. Future research will demonstrate, I'm sure, that I'd better leave the damn potato chips at the store. Behind glass. In the care of armed guards.