Let's not forget that for thousands of years the institution of marriage has been between a man and a woman. Until quite recently, in a limited number of countries, there has been no such thing as a marriage between persons of the same gender. Suddenly we are faced with the claim that thousands of years of human experience should be set aside because we should not discriminate in relation to the institution of marriage. When that claim is made, the burden of proving that this step will not undo the wisdom and stability of millennia of experience lies on those who would make the change.