From a letter by Queen Victoria to William Gladstone dated May 6, 1870,

The circumstances respecting the Bill to give women the same position as men with respect to Parliamentary franchise gives her an opportunity to observe that she had for some time past wished to call Mr Gladstone's attention to the mad & utterly demoralizing movement of the present day to place women in the same position as to professions -- as men; -- & amongst others, in the Medical Line.

And she is most anxious that it should be known how she not only disapproves but abhors the attempts to destroy all propriety & womanly feeling which will inevitably be the result of what had been proposed. The Queen is a woman herself -- & knows what an anomaly her own position is: -- but that can be reconciled with reason & propriety tho' it is a terribly difficult & trying one. But to tear away all the barriers which surround a woman, & to propose that they should study with men -- things which could not be named before them -- certainly not in a mixed audience -- would be to introduce a total disregard of what must be considered as belonging to the rules and principles of morality.

A similar logic underlies most arguments against gay marriage. Most people who oppose it do so because they feel its not appropriate, not right, not what they grew up with. To buttress up these arguments, they resort to the fanciful claim that if gay marriage is adopted, the institutions of our society will suffer grave consequences -- not so different from Queen Victoria's claim that equality between the sexes will induce a "total disregard...[of] the rules and principles of morality."