That raises the question: are some moral codes objectively better than others? I find it hard to answer. Intuitively, the response would be yes. Morality is objective. Some things are clearly wrong. "Murder," a friend of mine once argued, "is always morally wrong." But murder is, by definition, the immoral (or unjust, but in this case the adjectives are synonyms) killing of another creature. Saying "an immoral killing is immoral" is a tautology. But killing someone can be justified. It can be considered morally correct depending upon the circumstances under which it happens and, more importantly, depending on who's judging it to be moral or immoral. Self-defense, punishment, vengeance, casualty of war, etc have all been used as justifications for why a killing may be considered to be just or moral instead of murder.
But surely some overall moral codes, the collection of morals held together by a unifying theme, can be shown to be better than others. How would we even show this? How can we define better? Is it the code that results in one society having the largest possible population, or another society having the happiest population? Perhaps it's the code that allows one society's population the most "freedom," however you wish to define that word. Regardless, for one code to be objectively better than another, it must have some empirically testable dependent variable. As I have not been able to identify such a variable, nor have I yet seen an argument which strongly defends one that I can agree with, I tentatively conclude that no such variable exists.
The disturbing question is then raised: if all morality is equal, then how do we justify punishing those who do things we morally disagree with? All moral codes are equal, but only the morals which are widely agreed upon are enforceable. Therefore, even if your moral code found a killing you committed to be acceptable, if everyone else (or really, a sufficiently large number of people) found your action to be immoral, you would be considered to be a murderer, with all the weights and punishments attached.
Similarly, multiple people with very different moral codes could (and do) live harmoniously together as long as their moral codes produce similar outputs. One person's moral code could be defined as "what Jesus said in the New Testament," another could be "the ten commandments," and a third could be "do not harm another living person," and all three would probably agree on a wide variety of issues that would come up on whether or not an action that was taken was morally right or wrong.
As a final note, I used to believe that a moral code should be logically derived from a few axioms and be as thoroughly consistent as possible. I can think of no reason to defend that view, unless you believe hypocrisy is morally wrong (which, for the record, I do). However, at this point, society does seem to consider hypocrisy morally wrong, so I do think that any argument that relies on morality at this point should be internally consistent.
Over time, morality will continue to evolve and change. Things that we would regard as innocuous now will one day be considered reprehensible, and vice versa. For this reason, all laws need to be passed in such a way that they can be eventually discarded or abandoned.
The structure and style of this post's prose frustrates me. Though thematically, the ideas here are related, I seem to be making several arguments at once, and all of them poorly. I'll edit this later.
