This was a response in another thread, but it seemed to comprehensive--and while tangentially related to the topic, too far beyond its particular scope--to let languish there.
Much of the conflict between atheists and theists (to say nothing of the pantheists, panentheists, agnostics, and whomever else I haven't thought of)--when it's not snagged on political issues like same-sex marriage or DADT or abortion or sex education or teacher-led prayer or [insert religiously based political conflict here]--seems to center on a more elemental question: If absence or non-existence of deity is taken as the default position, from whence cometh rights and morals?
One can posit that natural rights exists if one comes from a Natural Law (as initially defined by Aquinas and codified, in the modern lexicon, by Locke) perspective, but if one does so, one needs to recognize that one is either making a theistic argument (like Aquinas) or a crypto-theistic argument (like Locke). That is, if there are transcendent and self-evident truths, this is indistinguishable, functionally, from deity; whether there is a being who ordained a set of rules by which we must abide or a set of pre-existent rules, ordained by no one, by which we must abide, we're still suggesting that the rules precede those ostensibly subject to them (us), and therefore transcend any desire of ours to let them "evolve" as society changes.
I would also add that if there are rights in nature, there are also laws in nature (not in the sense of gravity or entropy, but in the sense of the breeding imperative, survival of the fittest, and, ultimately, moral rules governing behavior that precede any organism that might "behave"). Taken to extremes, then, one needn't posit a deity to have a de facto theocracy; one might only suggest that the mere intuitive sensibility of a dictate means it comes from nature.
To put it more colloquially, if one can say that it's "self-evident" that we have the right to life, liberty, or the pursuit of happiness, one could as easily say that it's "self-evident" that homosexuality is wrong. As I don't believe the latter, it's worth analyzing the former.
So what are rights, and where do they come from? Well, first and foremost, I should say that rights are not created. They are yielded. To say that there is a right to life does not bequeath life; it is to be in the presence of one who is already alive, and agree not to take his/her life. To say that there is a right to liberty is to agree not to stifle someone's liberty. The two major properties these have in common are the offering of quarter and the presence of an agreement.
Of course, this matter goes far beyond rights; the whole question of human morality (and I should not that humans are NOT unique in their application of moral principle; one finds the regimentation of behavior according to principle in pretty nearly any species, from virus to bonobo to homo sapien). The uniformity of the core principles of human behavior--generalized proscriptions against lying, rape, murder, theft, and cheating (feel free to let me know if I've missed any; also, before anyone uses differences in the particulars to contradict this, know that while institutions of war, capital punishment, honor killings, cannibalism, or variations on these proscriptions with relation to gender, insider/outsider identification, or definition of property, it's pretty easy to demonstrate that these are differences of application, not of principle, in the same way that the differences between Quakerism and Calvinism do not make one "more Christian" than the other--though Calvinists would invariably find otherwise) would lead some to suggest that these are "received," as by a deity. Atheists, generally, would dismiss that (as would I), but too many of them (in my opinion and, in one of our less-rare-than-you-might-be-lead-to-believe moments of agreement, in Socrates1's opinion)
would still cop to the notion that these "rules" are self-evident, and occur naturally . . . which brings us back to Natural Law, which, again, implies theism.
What I would suggest, then, is that these principles are not self-evident, but are evident--arrived at through millennia of trial and error, negotiation, and revision. Which means, of course, that the application will continue to undergo such processes, presumably until we get it right . . . or possibly until we realize that constant revision is our lot.
Thus, while moral reasoning will have an individual basis (and changes in the moral structure of a society tend to arise by virtue of those members who oppose the current order--Siddhartha Gautama, Jesus Christ, the Marquis de Sade, Rousseau, Gandhi, Joan of Arc, Martin Luther, Jack Kerouac, Ibsen, Sartre, Camus, Genet, Shaw, Beckett, and so on) , moral enforcement is a function of agreement, and thus of the group. And from morality, we derive other systems of behavioral regulation--law (which is necessarily shallower than morality--morality grows from utility, but is not limited to it, while law, in my opinion, should be hobbled from addressing anything but what is required to keep the rights of the individual to be safe in person and property, and at "liberty" to succumb to the moral and ethical interests to whatever other groups, if any, he is born into or wishes to join--but, of necessity, more broadly applicable) and ethics (the relationship between morals and ethics is complex, subjectively defined, and, in my view, not really relevant to this discussion; feel free to run with it as a tangent, if you must).
In each case, the arbiter of these rules, once they're established, is the group; individuals and sub-groups therewithin provide the impetus of change. And interestingly enough, there is no group small enough that it has no sub-groups--even the nuclear family is often divided into factions. As such, while law tends to be regulated by "groups" to which we belong by geographic default or voluntary immigration/emigration (states, nation-states, cities, etc.), morals and ethics are hammered out among the hodge-podge of other groups--families, churches, neighborhoods, and such. Certain broad moral or ethical principles may, by default or tradition, be included tacitly within the essential character of a law-oriented entity (particularly a city or town, which is why a Seattle, WA will appear to have an obviously different moral, and not just legal, character than a Halifax, VA [there is such a place, right?]), and in some places you will even find moral principles directly codified into that law (to which one might reasonably object--I do).
Finally, you're likely to see some posters (wouldn't want to look like I was calling anyone out) insist that "society" is responsible for creating morals. I agree. The definition of "society," however, is extremely broad. Take note:
- The totality of social relationships among humans.
- A group of humans broadly distinguished from other groups by mutual interests, participation in characteristic relationships, shared institutions, and a common culture.
- The institutions and culture of a distinct self-perpetuating group.
- An organization or association of persons engaged in a common profession, activity, or interest: a folklore society; a society of bird watchers.
- The rich, privileged, and fashionable social class.
- The socially dominant members of a community.
- Companionship; company: enjoys the society of friends and family members.
- Biology. A colony or community of organisms, usually of the same species: an insect society.
[French société, from Old French, from Latin societās, fellowship, from socius, companion.]
Since this could refer to anything from the global community to the circle of friends you meet on Friday at the bar, suggesting that society has the right to regulate morality doesn't really say to whom, exactly, we confer that power. Granting that the correct definitions of words are tools of obfuscation used by we in the liberal elite, pointing that out might only lead to ridicule, but it's a risk we might all have to take.