How can you prove that it is because of extreme hatred or bad philosophy or bad religion that Jihad Joe thinks it's OK to crash planes into American skyscrapers? How do you know that he has the same moral perspective as you but is just horribly misguided? What's worst, how do YOU know that crashing planes isn't the RIGHT thing to do and it's YOUR moral perspective that is messed up? If this sounds far fetch a lot of people and churches in the world today believe capital punishment is wrong. What is the moral law for that?
These are rhetorical questions and I'm not trying to put you on the spot. I'm just trying to make a point, as the philosophers did, that if you took ten religious figures from ten different cultures (even the same culture) and asked them to compose a list of natural laws you'd get 10 different lists. Who would say the "Christian" viewpoint is correct out of those 10 lists?
God gave us the Bible and the Laws so we WOULD have a list. I doubt if you'd put a bunch of theologians in a room if you would come up with the the 10 commandments. Certainly our justice system doesn't seem to think so.
Natural law seems to me to be something to talk over around the water cooler but is impossible to know if it even exist. All indications are that it does not. We have the written 10 commandments and we want to discard them. Why would we think these would be ingrained in us?
It's pretty tough to prove hatred, but bad philosophy or bad religion are much easier to prove than emotion, because they can be better expressed in words and concepts which can be weighed against themselves(for self-consistency) and various self-evident truths and, if we share the same religion, the truths of revelation.
Now if you insist that there are no self-evident, shared truths across cultural or religious divisions, I'll again cite Augustine on the justice present among pirates. Though their sense of justice is woefully limited, being the justice only necessary for their survival, even this basic kind of justice is a good that transcends merely particular group interest: nobody likes being murdered. You pirates don't kill us, we civilized folk won't kill you.
What's worst, how do YOU know that crashing planes isn't the RIGHT thing to do and it's YOUR moral perspective that is messed up?
Let's get this back to the general principle I was defending, "the direct taking of innocent human life is wrong." I would say this is true by definition: an innocent person is by definition not guilty of a punishment, and thus doesn't deserve death, an objective evil. But I think I can anticipate your objection: Why think death is an evil? Might death not be good in some cases, where you're actually doing somebody a favor by killing him and freeing him from his miserable life? Isn't all this life-affirming silliness a product of Christianity? Maybe the gnostics were right, and the body is really a prison for the soul. Mass murder is really mass liberation!
Let's say for a moment that life really is an objective evil. Even if that were the case, one cannot take away something from somebody without his permission: you don't have clear title to another man's life. (Neither does the individual have clear title to his own life, one reason why suicide is morally problematic). I could go on and try to prove that having a title to something is a part of justice, but I think I've proven what I set out to do.
These are rhetorical questions and I'm not trying to put you on the spot. I'm just trying to make a point, as the philosophers did, that if you took ten religious figures from ten different cultures (even the same culture) and asked them to compose a list of natural laws you'd get 10 different lists.
I would argue there would be considerable overlap between those lists. You'd definitely get the bare minimum "pirate justice" necessary for the maintenance of society. People who have a death wish are few, and whole cultures with a death wish have already gone extinct.
Since you've brought up the Bible, may I point out to you that,as Budsizewski noted, St. Paul talks about the natural law? See Romans 2:13-16:
For not the hearers of the law are just before God: but the doers of the law shall be justified. For when the Gentiles, who have not the law, do by nature those things that are of the law; these, having not the law, are a law to themselves. Who shew the work of the law written in their hearts, their conscience bearing witness to them: and their thoughts between themselves accusing or also defending one another In the day when God shall judge the secrets of men by Jesus Christ, according to my gospel.