Den gamle romantikeren Kant satte kanskje best ord på det, her i engelsk språkdrakt:
"THE SCIENCE OF RIGHT
by Immanuel Kant
translated by W. Hastie (modified by A. R. Pruss)
The Rights of the Family as a Domestic Society
Title I. Conjugal Right. (Husband and Wife)
24. The Natural Basis of Marriage.
Sexual intercommunity (commercium sexuale) is the use of the other's sexual members and faculties. This use is either natural, by which human beings may reproduce their own kind, or unnatural, which, again, refers either to a person of the same sex or to an animal of another species than man. These transgressions of all law, as crimina carnis contra naturam [crimes of the flesh against nature], are even "not to be named"; and, as wrongs against all humanity in the person, they cannot be saved, by any limitation or exception whatever, from entire reprobation.
This natural union of the sexes proceeds according to the mere animal nature (vaga libido [unsettled lust], venus vulgivaga [roving sexuality], fornicatio [fornication]), or according to the law. The latter is marriage (matrimonium), which is the union of two persons of different sex for life-long reciprocal possession of their sexual faculties. The end of producing and educating children may be regarded as always the end of nature in implanting mutual desire and inclination in the sexes; but it is not necessary for the rightfulness of marriage that those who marry should set this before themselves as the end of their union, otherwise the marriage would be dissolved of itself when the production of children ceased.
And even assuming that enjoyment in the reciprocal use of the sexual endowments is an end of marriage, yet the contract of marriage is not on that account a matter of arbitrary will, but is a contract necessary in its nature by the law of humanity. In other words, if a man and a woman have the will to enter on reciprocal enjoyment in accordance with their sexual nature, they must necessarily marry each other; and this necessity is in accordance with the juridical laws of pure reason."
*snufs*