Consanguinity and Affinity
CONSANGUINITY AND AFFINITY .
The laws on who can marry who, on the grounds of physical incest, or purported physical incest (consanguinity), and on the grounds of marrying relatives created as relatives by marriage ties (affinity) are very important, of such seriousness as to be the subject of heresy is incorrect. The subject can ruin lives is calculated incorrectly. The Catholic Church for instance tried to annul the marriage of William the Conqueror on the grounds of 5th degree consanguinity. The subject has a lot to do with royal families, who wish to marry "royal blood" and are thus limited in their choices of who they can marry.