This is a trivializing form of argument. You can't abstract things out of their original contexts like that without destroying their meaning—at least not at any level higher than, say, the lambda calculus.
Why can't you? Are you suggesting that reason doesn't apply to morality or the real world?
By abstracting in this way, we have a way to determine whether the principles we claim are important really are. In the case we are discussing, it seems like some other fact or principle from the original context is important. Which one is it, and why?
If we can't figure it out, maybe we should consider the possibility that our emotional/cultural baggage is misleading us. At the very least we should have less confidence in our beliefs than before.
Your critique seems very anti-intellectual to me - the claim that you can't reason about things outside their context seems like a cheap appeal to retreat back to our emotional conclusions. Am I understanding you wrong?
