Re human rights, the UDHR seems like a reasonable place to start.

Your physicist friend was probably gay.

I’m dubious as to how the chemical process that we dub “love” is a firm basis for any set of morals. Why should we give it any particular meaning? I’m also fairly sure that love sets some people above others as far as the lover is concerned, so it isn’t really a good start for any sort of egalitarian system.
I’m less opposed to the idea of compassion, though, as that seems more linked to Dan Barker’s idea that a “morality based on reason” would be arrived at by attempting to “minimise harm”. However, I’m still concerned that an emotion forms the basis of such a morality, since I find it plausible that any two people, when faced with two different sorts of suffering, might consider one more dire than the other. How do you deal with these discrepancies between the people’s own morality to form the rules of a society? The only solution I see is to base consensus, which can be problematic.
I’m also tempted to ask, “Which universal human rights?”.
Panel 3 actually reminds me of a Physicist with whom I lived for a year at University. He was an atheist and was pretty firmly anti-gay – while, of course, railing at religion being unfair to women – as is another atheist friend of mine. To be fair, though, it’s always frustrated me that people of faith concentrate so much on homosexuality. The Qur’an seems to say that homosexual acts are a sin, but there’s nothing to suggest it’s the “worst sin ever”, to paraphrase the Simpsons. I’m fairly certain there are sins condemned far worse in the literature, but as far as the practitioners go, the anti-gay thing takes up far too much time.

Atheists rarely have a reason to be anti-gay — they have no god to tell them how terrible it is, so they are free to be themselves or allow others to do so. But being an atheist doesn’t make you any more or less likely to be gay. (It does make you more likely to be okay with it if you are gay, though.)

And, of course, reproduction is not the primary motivation for people falling in love these days. If it were, I’d have women lining up at my door (I make great kids.)

Lastly, I agree that adopting a religion means following the rules of that belief set, but, when it comes to homosexuality, that all too often results in tragedy. Too many gay men deny their sexuality because they believe it is wrong and that they can’t possibly be gay — consider Ted Haggard, Larry Craig, Gov. McGreevey, the WBC guy, and so on. (I wrote about this here: http://www.parentdish.com/2009/01/29/gay-kids-tell-their-stories-in-crisis ).

As for murderers, thieves, and priests — atheists are far more anti-murder than christians and muslims. (If I were a true bible-following christian, I would have had to kill each of my kids hundreds of times each.) The same is likely true of theft.

If you feel the need to adopt a religion then I’m afraid its ‘moral code’ comes as part of the package. What about the ‘human rights’ of murderers and thieves? Shouldn’t they get to be priests too?