Yes, your example makes no sense because it's pointless. Just because two people cannot reproduce doesn't mean they are wrong or unnatural. They actually COULD create life. You're missing MY point which is they JUST DON'T CHOOSE TO. Some people don't want children... I guess they're wrong and unnatural and shouldn't be allowed to marry, right? How 'bout no. Gays can't change what they are -- they don't choose to be gay, but they are, it's genetical. They can go out and create life if they wanted to, but they don't. Some even do, just to reproduce. As I said earlier, some handicapped/retarded people cannot reproduce, that doesn't make them "wrong" and it shouldn't mean they aren't allowed to marry. Read LDV's post... It proves your theory about reproduction wrong.
the power of accurate observation is commonly called cynicism by those who have not got it. george bernard shaw