X. Marriage.
Roman citizens are bound together in lawful matrimony when they are united according to law, the males having attained the age of puberty, and the females a marriageable age, whether they are fathers or sons of a family; but, of the latter, they must first obtain the consent of their parents, in whose power they are.
For both natural reason and the law require this consent; so much so, indeed, that it ought to precede the marriage. Hence the question has arisen, whether the daughter of a madman could be married, or his son marry? And as opinions were divided as to the son, we decided that as the daughter of a madman might, so may the son of a madman marry without the intervention of the father, according to the mode established by our constitutio.
1. We may not marry every woman without distinction; for with some, marriage is forbidden. Marriage cannot be contracted between persons standing to each other in the relation of ascendant and descendant, as between a father and daughter, a grandfather and his granddaughter, a mother and her son, a grandmother and her grandson; and so on, ad infinitum.
And, if such persons unite together, they only contract a criminal and incestuous marriage; so much so, that ascendants and descendants, who are only so by adoption, cannot intermarry; and even after the adoption is dissolved, the prohibition remains. You cannot, therefore, marry a woman who has been either your daughter or granddaughter by adoption, although you may have emancipated her.
2. There are also restrictions, though not so extensive, on marriage between collateral relations. A brother and sister are forbidden to marry, whether they are the children of the same father and mother, or of one of the two only.
And, if a woman becomes your sister by adoption, you certainly cannot marry; but, if the adoption is destroyed by emancipation, you may marry her; as you may also, if you yourself are emancipated. Hence it follows, that if a man would adopt his son-in-law, he ought first to emancipate his daughter; and if he would adopt his daughter-in-law, he ought previously to emancipate his son.
3. A man may not marry the daughter of a brother, or a sister, nor the granddaughter, although she is in the fourth degree. For when we may not marry the daughter of any person, neither may we marry the granddaughter. But there does not appear to be any impediment to marrying the daughter of a woman whom your father has adopted; for she is no relation to you, either by natural or civil law.
4. The children of two brothers or two sisters, or of a brother and sister, may marry together.
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