Life occurred on earth with one simple rule. It needs nourishment. Life originated into complex forms but we still need a source of food. We have still not evolved past the basic needs of survival. After-all, survival is the mother of evolution.
There is one thing that we humans need after food is the nourishment for our souls. It is the basic need of understanding the universe and life as it is. It is something everyone is curious about. So how is this need for mental nourishment going to be fulfilled? What would be the source of the nourishment for our soul?
God certainly has provided enough for physical nutrition of life but what is there for the nourishment of the human soul? Most of us ponder upon the question that there has to be some guidance from God's side, so where is it?
I believe that the guidance is imbibed into one's self and we call it wisdom. God has created a system in which good will bring good and bad will bring bad. It is inevitable in the long run if we take into consideration that human race is one. People who do not see this truth are disturbed by the complexities of life and nature and become all sorts of non-believers. No one, i believe, would do an evil deed if it had to harm his self. That is the basic rule of survival. No one wants to harm himself. If one would know that evil brings harm to himself apart from harming others, he would certainly not do the evil deed.
That is why i think it is important for everyone to know and rely on the source of guidance which is his/her mind's wisdom. Wisdom is nothing but the logic that sets apart right from wrong.