When I first moved to California, I had the choice of renting a 700 square foot apartment for $650 per month and an 850 square foot apartment for $550 per month. Both were in the same building. The larger and less expensive one even had a better view.

I was puzzled by the bargain until the landlord explained to me that there had been an “unfortunate incident” in the larger apartment. As a result, no one was willing to rent it. It was as if the apartment was contaminated.

Although I didn’t know it at the time, people were exhibiting what Wray Herbert calls the “cooties heuristic,” named after the imaginary disease that U.S. school kids think they will get by kissing members of the opposite sex. Herbert claims we think in extremes when it comes to the purity of our food. Virtually anything added to natural food causes the food to have cooties, reducing its appeal. This helps explain why “nothing artificial” and “no additives” are such powerful marketing devices.

Read full blog post here.