[1] It is doubtless true, as anthropologists have pointed out, that in the history of the race “marriage is rooted in the family rather than the family in marriage” (Westermarck: History of Human Marriage, p. 22); but in that conscious experience of the individual with which law and ethics are especially concerned, this relationship is reversed, and the family originates in marriage (see [Family], and allied headings).
[2] The restrictions are enumerated in the following lines:—
| Error, Conditio, Votum, Cognatio, Crimen, Cultus, Disparitas, Vis, Ordo, Ligamen, Honestas, Aetas, Affinis, si Clandestinus et Impos, Raptave sit mulier nec parti reddita tutae. |
[3] Canon lxi. Aut qui ex propria consanguinitate aliquam, aut quam consanguineus habuit ... duceret uxorem ... incestos esse non dubitamus (Mansi Conc. viii. p. 336). According to the canon law “affinity” is the relation between two persons of whom one has had commerce, licit or illicit, with a relation of the other.
[4] The civil law counts, in the direct line, as many degrees as there are generations between the parties; e.g. the son is in regard to his father in the 1st degree, the grandson in the 2nd, and vice versa. In the collateral line it computes degrees by generations, i.e. from one of the relations to the common ancestor, without including him or her, and from him or her back to the other relation; e.g. two brothers are in the 2nd degree of relationship to one another, uncle and nephew in the 3rd, cousins-german in the 4th.
The canon law, which in this case derives from the old Germanic law, has the same computation as regards the direct line. In the case of collateral relations, however, it differs, having two rules: (1) In the case of equal line—i.e. when the collaterals are equally removed from the common progenitor, it reckons the same number of degrees between the collaterals as between one of them and the progenitor; e.g. brothers are related in the 1st degree, while cousins-german are related in the 2nd degree because they are two generations from the common grandfather. (2) In the case of unequal line—i.e. when the collaterals are unequally removed from the common ancestor, the degree of their relationship is that of the most remote from the common progenitor; e.g. uncle and niece are related in the 2nd degree—i.e. that of the niece to the grandfather.
The civil computation was furiously attacked by canonists as tending to laxity (see Peter Damianus, “De parentelae gradibus,” in Migne, Patrol. Lat. cxlv. 191, &c.).
[5] Innocent III. also decided that the husband’s relations were not related to those of the wife, and vice versa, thus establishing the rule that “affinity does not breed affinity” (affinitas non parit affinitatem).
[6] This is fixed by the canon law at 14 for a male, 12 for a female. If, however, owing to the precocious physical development of a girl, the marriage has been consummated before she has reached this age, it cannot be nullified.