By perfect world I mean that every person and all the different beliefs or political parties or the different cultures around the world, they're all useful.
I think they are not all useful, but I agree to what you say subsequently that they are all natural.
From a perspective of a perfect society, Muslim extremists or child molesters are not useful. But they exist because their mindset also belongs to the pool of possible human mind sets and thus is a product of nature or evolution or whatever you call it.
However, we normally don't accept this but attempt to make our society better, by rules and laws, which also includes religious laws like the 10 commandments, and thus try to filter our mindsets we consider 'not useful'. This way, we try to correct nature.
