What is “the” purpose of marriage? Are you suggesting there’s only one?
Take another peek at the history of civil marriage, especially the precedent for judicial determinations.
Since you’re admittedly unaware of the history of same-sex marriage, here’s another useful link.
http://en.wikipedia.org/wiki/Same-sex_marriage
The purpose of marriage is to bond people of the opposite sex together. There have been variations on that theme throughout history, but until the total loss of our common sense in recent years, marriage has never been between people of the same sex.
Take another peek at the history of civil marriage, especially the precedent for judicial determinations.
Well then, why don't we just do away with voting and legislatures entirely? We could slap a sign reading "oracle" in front of the nearest judge and just allow him to run the country by fiat.
Since youre admittedly unaware of the history of same-sex marriage, heres another useful link.
If you think same-sex "marriage" has any historical basis in Western civilization, you're badly mistaken. In other words, you're badly mistaken.