Going easy on ourselves also reflects a key cognitive fact: we judge ourselves by our internal motives and everyone else by their external actions. And thus, in considering our own misdeeds, we have more access to mitigating situational information. This is straight out of Us/Them–when Thems do something wrong, it’s because they’re simply rotten; when Us-es do it, it’s because of an extenuating circumstance and “Me” is the most focal Us there is, coming with the most insight into internal state. Thus, on this cognitive level, there is no inconsistency or hypocrisy and we might readily perceive a wrong to be mitigated by internal motives in the case of anyone’s misdeeds. It’s just easier to know those motives when we are the perpetrator.
The adverse consequences of this are wide and deep. Moreover, the pull towards judging yourself less harshly than others easily resists the rationality of deterrence. As Ariely writes in his book, “Overall, cheating is not limited by risk; it is limited by our ability to rationalize the cheating to ourselves”.