Smart and honest

From Clever Enough to Tell the Truth by Bradley J. Ruffle and Yossef Tobol.

We conduct a field experiment on 427 Israeli soldiers who each rolled a six-sided die in private and reported the outcome. For every point reported, the soldier received an additional half-hour early release from the army base on Thursday afternoon. We find that the higher a soldier’s military entrance score, the more honest he is on average. We replicate this finding on a sample of 156 civilians paid in cash for their die reports. Furthermore, the civilian experiments reveal that two measures of cognitive ability predict honesty, whereas self-report honesty questions and a consistency check among them are of no value. We provide a rationale for the relationship between cognitive ability and honesty and discuss the generalizability of this result.

How does this relate to Gregory Clark's thesis that there is upward evolutionary pressure not just on IQs but on prosocial behaviors (such as honesty)? And of course this ties in to Dierdre McCloskey's work The Bourgeois Virtues linking prosocial behaviors and productivity.

Or perhaps this is just evidence that smarter people have a better understanding that risk-adjusted dishonesty, over the long term, has a negative return? Better to be consistently honest, despite short term disadvantages, because the long term advantages of consistent honesty are higher?