I forgot to write about Rif & Anna and my experiment performed during my trip to Boston. Having recently read Blink, in which Malcolm Gladwell writes of the Pepsi Challenge, we decided to test ourselves and see if we could tell the difference between Coke and Pepsi without looking.

The short summary is this: it’s damn hard to tell the difference.

The longer version is that if you just compare a sip of one against a sip of the other, it’s harder to tell them apart than you might think (try it), but not impossible. Statistics is on your side, too, as you can make a more educated guess knowing that one of the glasses is Coke and the other Pepsi. Gladwell suggests adding a third glass in to the mix, of either one (but don’t tell the test subject) and trying to identify all three.

It’s tough. I got all three of mine right, but I suspect there was some luck involved, Rif got one out of three right, and Anna (if I remember correctly) didn’t taste enough of a difference to make a guess. I was pretty surprised how close the two tasted in the experiment. Gladwell writes that on some scale used by the food industry to rank how close two foods are in taste, Coke and Pepsi are just one unit apart, and now I believe it.