This is one of those questions that have no short answer, as it depends who the questions is posed to.
The first group believes that all morality originates from god. God has decided what is good and what is bad. To these people, it is inconceivable that goodness can exist outside the realm of a theistic world. To them, all goodness is sourced at god, and all evil, from the Satan. And those that are good without believing in god, are so because they have learned morality from their environment of theistic neighbors.
Then there are those that have a theistic, secular bent of mind. To them, man can be good without a god to prescribe moral behavior. They are convinced that goodness is part of human nature, just as evil is. But choosing the right path them just gets them closer to god, their definition of ultimate reality.
The third group of people believe that morality does not require the existence of god for they have arrived at the realization that morality and altruism is a by-product of evolution. They have observed that society has prescribed certain coded of conduct to coexist peacefully. And therefore, each society has derived specific codes that might seem strange to other societies, and hence the concept of relative morals. Cannibalism might seem extremely immoral to the west, but seem perfectly natural to the tribes of Java and Sumatra. These tribes consider the World Wars that have killed hundreds of thousands of people to be a crime.
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http://www.ted.com/talks/lang/eng/emmanuel_jal_the_music_of_a_war_child.html
15 years ago