The theory of devolution
If life evolved by means of natural selection, all bad human traits must have been preferentially selected at some point. This would make the world inherently both bad and good, instead of entirely good. Coping with reality is easier when imagining that life devolves from a divine state. That is to say, it is easier to cope with the thought that all bad traits in man are errors instead of features.
In some parts of the contemporary world the populace has accepted that life was developed by natural selection. But their thoughts and behaviour suggests that in their hearts they still believe that evil is of an otherwordly origin.
The first category of devolution theories encompasses most religious worldviews. That before creation was ushered into existence, the cosmos was in a perfect harmonic state of truth and reason. Then, due to some catastrophic error, man was banished from eden (i.e. devolved) to the filth of the carnal plane. And life is a struggle to get back to a worldly state where evil is once again abscent.
Secondly, the secular adaptaion of this very same principle albeit with a slightly different twist. To cope with living in a secular society we must imagine that evil is not being preferentially selected in society the way it has in life. We must believe that life evolves away from evil towards truth, order, and reason; and that these virtues alone are being selected at present.
While in truth, there most probably has been a state on earth were no living thing was capable of lying in any sense. Where nothing could intentionally be evil or deceive. But life has evolved away from this state. Indeed, creation rejected a world of truth and reason to make way for a world of darkness and deception.
So in contemporary society, people still have an intrinsic need to devolve, a need to "abort" evil by regressing to a more primitive state. paradoxically, this devolution is labeled as progress. If by chance a more truthy world could be attained, it would make sense for it to evolve past it once again, making the strife for justice and reason seem like a sisyphean ordeal.
Likewise, this thought-error must have been selected. The reason why the selective direction of life has hitherto always been inverted in our mental representation of the world must conform with the direction of life, with destiny. The first cell has been mercyful in allowing us to perceive the world in this inverted way.