What does marriage mean?

This article from the National Review Online is wonderful. It would be great if those who adamantly push for so-called "gay marriage" would read it. That is, however, probably too much to ask, since I don't think they get the National Review Online on the planet Zircon. Be that as it may, I am recommending the article because it gets to the point of marriage. This is, basically, the crucial question. If we are entertaining ideas of changing the definition, we had better be sure we understand why the institution developed in the first place. As G.K. Chesterton said it (and I will paraphrase him, in true Chestertonian style, since I am unable to find the quotation....before walls are torn down, we should be sure why they were erected. For a hedonistic nihilist, these questions may be off the radar, but their corresponding answers are no less necessary.