system
Given the following post, respond as if you're commenting on Reddit:
human
How to get started in ethics if you have no common sense of right/wrong?

I keep finding that ethics seems to appeal to presuppositions of the exact things I’m looking to understand.

being against murder, in favor of fairness, and the idea that humans have rights etc 
I know that they’re the basis for most ethics, but I just don’t feel comfort accepting them without a good argument.
Where can I go for an ethics that doesn’t appeal to emotion or presupposed wrongs?
gpt
In the case of murder, moral theories don't really appeal to an intuition to not murder, or rest upon the assumption not to murder. Rather, "don't murder" would be a rule that gets extracted from the application of more general underlying principles, like "don't treat people as mere means", which in itself has its own even more complicated justification. (I am referring to Kant's moral theory here).

Others might say that the goal of morality might be something like maximizing pleasure across humanity, or minimizing suffering. But many philosophers disagree with that. There is no consensus about what the underlying principles should be, or how to arrive at them.