Reply #5: The language is originally from a case about sterilization, if I recall correctly. [View All]

But even then the right is not "fundamental to our existence and survival" in the sense that violating it will lead to our extinction: the continuation of the human species is not seriously imperiled if a small minority of people are forcibly sterilized.

I'd suggest that the right way to read the phrase is as a reference to the centrality of romantic and sexual desire and expression to our lives: because they are (in general) important to our survival as a species, they are naturally important, fundamental parts of our lives, part of our right of liberty. For the government to intervene in that expression without a very good reason is a violation of our rights, not because it somehow threatens the propagation of our species, but because it interferes in our right to freely organize something basic to who we are as biological creatures.

And that certainly applies to same-sex marriage, too.