I was using science as an example of something the truths of which are universal--thus "objective."
Okay, that's sort of what I thought you meant, but I wanted to be sure. Still, I'm not sure I totally agree with your statement (although I understand what you were getting at). My understanding of science is that the only "universal truths" in science are the concrete data points from which science derives explanatory theories. Simplistically, a rock is a rock is a rock. Science itself, or perhaps better said the result of the scientific process, is actually a concensus. IOW, it's not Truth (with a capital "T"), and often may not even be truth (small "t"). It may represent the best available explanation, but as such it is open to and often subject to modification. You can't modify truth, by definition. Which is why, philosophically, I have difficulty saying the words truth and science in the same breath.
Here is the way I understand "objective morality." Morality is a system in which a good action is good in itself, apart from consequences. To be honest (as an example) is a good action in itself. There are cases, of course, when literal honesty is not so good--when a murderer asks you which way a man has gone--but in such cases the honesty principle is superceded by another, higher virtue (compassion for victims). So we have higher and lower virtues. But those cases when one duty is superseded by another does not invalidate the honesty principle at all.
Okay, I think we're coming to the heart of the issue here. Nicely said. My position is that there is no evidence for the existence of objective morality. There may, OTOH, be an objective behavioral ethic (what I've termed "normative behavior") based on how the species evolved. Michael Ruse calls it a "meta-ethic". However, I think it would be very difficult to prove an intrinsic status (i.e., morality) to an action beyond what we impute to it. You've more or less stated this yourself: you were unable to discuss objective morality without using such subjective value terms as "good", for instance. Indeed, even in the example of honesty which you used to illustrate your point, you later said that honesty in some circumstances may NOT be the best policy - it depends on extrinsic factors. How, therefore, can honesty - or any other attribute we consider "moral" for that matter - be universal or objective if it isn't universally applicable?
Now, if you were to put honesty in the context of game theory, you CAN make a case that honesty may be the best policy in most circumstances - IOW, it can be considered normative. Google on Iterated Prisoner's Dilemma or Tit-for-Tat strategies for examples of what I mean. In short, honesty is the best policy not because it is intrinsically "moral", but rather because it tends in general to maximize benefit to the one being honest - another example of Hamilton's Rule.
Now there are moral systems such as utilitarianism which I think we can refute. Old cranky person has lots of money; why not kill this person and give money to many starving children? According to utilitarianism, this is a good action.
Here we get to the important part: our "instincts" (if you will) tell us that it will not do to kill the old cranky person, no matter how useless they are and no matter how much it will benefit the group.
Now the question is, for me, whether that "instinct" that tells me that utilitarianism is fundamentally flawed is my perception of objective morality, or just something personal or cultural and thus relative and subjective.
An interesting example, and quite revealing. The short answer is: the society in which you were raised frowns upon murdering old rich cranky people. However, there have been societies where, because of resource restrictions, sacrificing old cranky people has been considered moral (one example is the pre-modern-era Ainu of Japan - see, for example, Kelly, WW 1991, "Directions in the Anthropology of Contemporary Japan", AnnRevAnthro, 20:395-431). IOW, the "instinct" you cite when you personally contemplate such action is a product of
your society, not an intrinsic, objective fact. (I admit ancestor sacrifice is uncommon - the waaaay more common view of old cranky people is that they are a net benefit to the group because of their experience, and are venerated simply for surviving long enough to get old in the first place.)
What might be a more interesting excercise is to try and determine if there are globally recognizable normative behaviors upon which we can build a Ruse-ian metaethic theory.
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