I firmly believe there is good and evil in the world. Since I accept that, I also have to believe there are two diametrically opposed forces in the world. Good=god and evil=Satan. I re-read MERE CHRISTIANITY, by C.S. Lewis, recently. This entry is purely inspired by him. I'll note page numbers from the 1996 Touchstone edition of MERE CHRISTIANITY. I would recommend it to anyone. It's a great book, which has definitely provoked all sorts of thought.
Lewis says that any morality (a convention of what is good and evil) held by anyone is held up to judgment (p.25). So if you say one moral standard is better than another, you are holding both standards up to something else to judge them by (P.25). That something else is a honest to goodness universal standard of good (p.25). Lewis uses the example of Nazism versus anything else (p.25). If Nazism is wrong compared to some other way of life, both of them are evaluated by a third, objective standard which is better than both the compared items (P. 25). It is the ideal standard that all others are judged by.
For instance, let's look at stealing.
Lewis mentions the argument that social convention dictates what is right and wrong (P. 24). Stealing is considered evil only because of social convention. One cannot steal because it creates disharmony within a social group.
Not necessarily. A social group comes together because they have common interests, and probably common values. In other words, a society comes together with like-minded individuals. They share the same values. One of those values that everyone recognizes in that society is that stealing is wrong. Take away the society, and stealing would still be wrong.
Granted, stealing is wrong only in the proper context. Lewis also points out that for every human urge, there is a time and place for it (P. 24). There are times when stealing is probably justified. Stealing food from an enemy in war is justified, for instance.
The point is, each act is judged as right or wrong by some outside, objective standard that the act is held up to.
It stands to reason, then, there is something out there which creates a universal perception of right and wrong. If right and wrong is not a social convention, then something in the universe decrees it.
That something would be God, would it not?