"Principle 5. Our modern skulls house a stone age mind.

Natural selection, the process that designed our brain, takes a long time to design a circuit of any complexity. The time it takes to build circuits that are suited to a given environment is so slow it is hard to even imagine -- it's like a stone being sculpted by wind-blown sand. Even relatively simple changes can take tens of thousands of years.

The environment that humans -- and, therefore, human minds -- evolved in was very different from our modern environment. Our ancestors spent well over 99% of our species' evolutionary history living in hunter-gatherer societies. That means that our forebearers lived in small, nomadic bands of a few dozen individuals who got all of their food each day by gathering plants or by hunting animals. Each of our ancestors was, in effect, on a camping trip that lasted an entire lifetime, and this way of life endured for most of the last 10 million years. "

Think about that the next time you are in a difficult mediation - what are these two numb skulls really trying to solve?

Using the camping trip analogy, I think the campers are trying to figure out a way to "fairly" divide the rabbit or deer; the handful berries or the few gathered roots in a way that: (1) will incentivize those able to hunt & gather to continue doing so (divide according to merit); (2) will permit the entire tribe to survive, including those too young or old to work for a living (divide according to need); and, (3) will permit differences of opinion about how best to make these decisions to be resolved without undue bloodshed.

Distributive and procedural justice, no?

The authors have an elegant proposal about how to defeat the wason effect; the tendency to confirm the truth of A implies B by looking for instances of when A and B are true.

Confirmation bias is often at the route of all bad decision making.

The authors note that if we change the conditional to Reward A, if Obligation/Requirement B, then people do much better: they know to look for A and not B, which the authors describe as looking for cheaters. (I disagree with their interpretation of their results, but not with the results.)

The author's suggestion is that we are much better at getting the logically correct answer on restricted type of conditionals, involving rewards and obligations. I find this convincing, and hope to see how to use it to combat confirmation bias.

As to the suggestion about procedural and distributive justice, I think those notions developed fairly late in our development. Just look at all the cultures who cannot figure out that a line-up is the best way to distribute scarce resources. Our old brain is telling us to rush to the front, effectively preventing most of us from getting anything in a timely manner.

See The Cost of Cutting in Line at HBS Working Knowledge here -- http://hbswk.hbs.edu/item/5319.html

Vickie