> There is a substantive difference between the sexes
> that could rationally limit what combination should
> be allowed to get married
Interesting. Could you expand on what those differences are, that might yield rational reasons?Also, please could you let me know if they extend to: couples where one or both are infertile; couples where one or both partners have a genetic intersex conditions, such as Klinefelter syndrome; couples where one or both partners had gender reassignment shortly after birth due to medical intervention; couples where both partners are living as men, but one was born female, but no surgery has been performed; as the before, but surgery has occurred; couples where medical accident has led to removal of genitalia; completely asexual male/female couples who have decided they wish to live together and support each other.
Also any links to your research in this area.