Of the Impediment of Affinity

Of the Impediment of Affinity — St. Thomas Aquinas asks: Whether a person contracts affinity through the marriage of a blood-relation?; Whether affinity remains after the death of husband or wife?; Whether unlawful intercourse causes affinity?; Whether affinity is caused by betrothal?; Whether affinity is a cause of affinity?; Whether affinity is an impediment to marriage?; Whether affinity in itself admits of degrees?; Whether the degrees of affinity extend in the same way as the degrees of consanguinity?; Whether a marriage contracted by persons with the degrees of affinity or consanguinity should always be annulled?; Whether it is necessary to proceed by way of accusation for the annulment of a marriage contracted by persons related to each other by affinity or consanguinity?; Whether in a suit of this kind one should proceed by hearing witnesses in the same way as in other suits?.

We must consider next the impediment of affinity. Under this head there are eleven points of inquiry:

Article 1: Whether a person contracts affinity through the marriage of a blood-relation?

Husband and wife are made one flesh. Therefore if the husband is related in the flesh to all his kindred, for the same reason his wife will be related to them all.

Further, this is proved by the authorities quoted in the text (Sent. iv, D, 41).

A certain natural friendship is founded on natural fellowship. Now natural fellowship, according to the Philosopher (Ethic. viii, 12), arises in two ways; first, from carnal procreation; secondly, from connection with orderly carnal procreation, wherefore he says (Ethic. viii, 12) that the friendship of a husband towards his wife is natural. Consequently even as a person through being connected with another by carnal procreation is bound to him by a tie of natural friendship, so does one person become connected with another through carnal intercourse. But there is a difference in this, that one who is connected with another through carnal procreation, as a son with his father, shares in the same common stock and blood, so that a son is connected with his father's kindred by the same kind of tie as the father was, the tie, namely of consanguinity, albeit in a different degree on account of his being more distant from the stock: whereas one who is connected with another through carnal intercourse does not share in the same stock, but is as it were an extraneous addition thereto: whence arises another kind of tie known by the name of "affinity." This is expressed in the verse:

Marriage makes a new kind of connection,

While birth makes a new degree,

because, to wit, the person begotten is in the same kind of relationship, but in a different degree, whereas through carnal intercourse he enters into a new kind of relationship.

Article 2: Whether affinity remains after the death of husband or wife?

Affinity is caused by consanguinity. Now consanguinity binds persons together for all time as long as they live. Therefore affinity does so also: and consequently affinity (between two persons) is not dissolved through the dissolution of the marriage by the death of a third person.

A relation ceases in two ways: in one way through the corruption of its subject, in another way by the removal of its cause; thus likeness ceases when one of the like subjects dies, or when the quality that caused the likeness is removed. Now there are certain relations which have for their cause an action, or a passion or movement (Metaph. v, 20): and some of these are caused by movement, through something being moved actually; such is the relation between mover and moved: some of them are caused through something being adapted to movement, for instance the relations between the motive power and the movable, or between master and servant; and some of them result from something, having been moved previously, such as the relation between father and son, for the relation between them is caused not by (the con) being begotten now, but by his having been begotten. Now aptitude for movement and for being moved is transitory; whereas the fact of having been moved is everlasting, since what has been never ceases having been. Consequently fatherhood and sonship are never dissolved through the removal of the cause, but only through the corruption of the subject, that is of one of the subjects. The same applies to affinity, for this is caused by certain persons having been joined together not by their being actually joined. Wherefore it is not done away, as long as the persons between whom affinity has been contracted survive, although the person die through whom it was contracted.

Article 3: Whether unlawful intercourse causes affinity?

He who is joined to a harlot is made one body (1 Cor. 6:16). Now this is the reason why marriage caused affinity. Therefore unlawful intercourse does so for the same reason.

Further, carnal intercourse is the cause of affinity, as shown by the definition of affinity, which definition is as follows: Affinity is the relationship of persons which results from carnal intercourse and is altogether void of blood-relationship. But there is carnal copulation even in unlawful intercourse. Therefore unlawful intercourse causes affinity.

According to the Philosopher (Ethic. viii, 12) the union of husband and wife is said to be natural chiefly on account of the procreation of offspring, and secondly on account of the community of works: the former of which belongs to marriage by reason of carnal copulation, and the latter, in so far as marriage is a partnership directed to a common life. Now the former is to be found in every carnal union where there is a mingling of seeds, since such a union may be productive of offspring, but the latter may be wanting. Consequently since marriage caused affinity, in so far as it was a carnal mingling, it follows that also an unlawful intercourse causes affinity in so far as it has something of natural copulation.

Article 4: Whether affinity is caused by betrothal?

Pope Alexander (cap. Ad audiendem, De spons. et matrim.) forbade a certain woman to marry a certain man, because she had been betrothed to his brother. Now this would not be the case unless affinity were contracted by betrothal. Therefore, etc.

Just as a betrothal has not the conditions of a perfect marriage, but is a preparation for marriage, so betrothal causes not affinity as marriage does, but something like affinity. This is called "the justice of public honesty," which is an impediment to marriage even as affinity and consanguinity are, and according to the same degrees, and is defined thus: "The justice of public honesty is a relationship arising out of betrothal, and derives its force from ecclesiastical institution by reason of its honesty." This indicates the reason of its name as well as its cause, namely that this relationship was instituted by the Church on account of its honesty.

Article 5: Whether affinity is a cause of affinity?

There are two ways in which one thing proceeds from another: in one way a thing proceeds from another in likeness of species, as a man is begotten of a man: in another way one thing proceeds from another, not in likeness of species; and this process is always towards a lower species, as instanced in all equivocal agents. The first kind of procession, however often it be repeated, the same species always remains: thus if one man be begotten of another by an act of the generative power, of this man also another man will be begotten, and so on. But the second kind of procession, just as in the first instance it produces another species, so it makes another species as often as it is repeated. Thus by movement from a point there proceeds a line and not a point, because a point by being moved makes a line; and from a line moved lineally, there proceeds not a line but a surface, and from a surface a body, and in this way the procession can go no further. Now in the procession of kinship we find two kinds whereby this tie is caused: one is by carnal procreation, and this always produces the same species of relationship; the other is by the marriage union, and this produces a different kind of relationship from the beginning: thus it is clear that a married woman is related to her husband's blood-relations not by blood but by affinity. Wherefore if this kind of process be repeated, the result will be not affinity but another kind of relationship; and consequently a married party contracts with the affines of the other party a relation not of affinity but of some other kind which is called affinity of the second kind. And again if a person through marriage contracts relationship with an affine of the second kind, it will not be affinity of the second kind, but of a third kind, as indicated in the verse quoted above (). Formerly these two kinds were included in the prohibition, under the head of the justice of public honesty rather than under the head of affinity, because they fall short of true affinity, in the same way as the relationship arising out of betrothal. Now however they have ceased to be included in the prohibition, which now refers only to the first kind of affinity in which true affinity consists.

Article 6: Whether affinity is an impediment to marriage?

It is written (Lev. 18:8): "Thou shalt not uncover the nakedness of thy father's wife." Now she is only affine. Therefore affinity is an impediment to marriage.

Affinity that precedes marriage hinders marriage being contracted and voids the contract, for the same reason as consanguinity. For just as there is a certain need for blood-relations to live together, so is there for those who are connected by affinity: and just as there is a tie of friendship between blood-relations, so is there between those who are affine to one another. If, however, affinity supervene to matrimony, it cannot void the marriage, as stated above ().

Article 7: Whether affinity in itself admits of degrees?

Affinity is caused by consanguinity. Therefore all the degrees of affinity are caused by the degrees of consanguinity: and so it has no degrees of itself.

A thing does not of itself admit of being divided except in reference to something belonging to it by reason of its genus: thus animal is divided into rational and irrational and not into white and black. Now carnal procreation has a direct relation to consanguinity, because the tie of consanguinity is immediately contracted through it; whereas it has no relation to affinity except through consanguinity which is the latter's cause. Wherefore since the degrees of relationship are distinguished in reference to carnal procreation, the distinction of degrees is directly and immediately referable to consanguinity, and to affinity through consanguinity. Hence the general rule in seeking the degrees of affinity is that in whatever degree of consanguinity I am related to the husband, in that same degree of affinity I am related to the wife.

Article 8: Whether the degrees of affinity extend in the same way as the degrees of consanguinity?

A woman is connected with me by affinity from the very fact that she is married to a blood-relation of mine. Therefore in whatever degree her husband is related to me by blood she is related to me in that same degree by affinity: and so the degrees of affinity should be reckoned in the same number as the degrees of consanguinity.

Since the degrees of affinity are reckoned according to the degrees of consanguinity, the degrees of affinity must needs be the same in number as those of consanguinity. Nevertheless, affinity being a lesser tie than consanguinity, both formerly and now, a dispensation is more easily granted in the more remote degrees of affinity than in the remote degrees of consanguinity.

Article 9: Whether a marriage contracted by persons with the degrees of affinity or consanguinity should always be annulled?

Consanguinity and affinity forbid the contracting of a marriage and void the contract. Therefore if affinity or consanguinity be proved, the parties should be separated even though they have actually contracted marriage.

Since all copulation apart from lawful marriage is a mortal sin, which the Church uses all her endeavors to prevent, it belongs to her to separate those between whom there cannot be valid marriage, especially those related by blood or by affinity, who cannot without incest be united in the flesh.

Article 10: Whether it is necessary to proceed by way of accusation for the annulment of a marriage contracted by persons related to each other by affinity or consanguinity?

Whatever is unlawful can be denounced. But the marriage of relatives by affinity and consanguinity is unlawful. Therefore it can be denounced.

Accusation is instituted lest the guilty be tolerated as though they were innocent. Now just as it happens through ignorance of fact that a guilty man is reputed innocent, so it happens through ignorance of a circumstance that a certain fact is deemed lawful whereas it is unlawful. Wherefore just as a man is sometimes accused, so is a fact sometimes an object of accusation. It is in this way that a marriage is denounced, when through ignorance of an impediment it is deemed lawful, whereas it is unlawful.

Article 11: Whether in a suit of this kind one should proceed by hearing witnesses in the same way as in other suits?

Witnesses are called in a suit in order to give the judge evidence concerning matters of doubt. Now evidence should be afforded the judge in this suit as in other suits, since he must not pronounce a hasty judgment on what is not proven. Therefore here as in other lawsuits witnesses should be called.

In this kind of lawsuit as in others, truth must be unveiled by witnesses: yet, as the lawyers say, there are many things peculiar to this suit; namely that "the same person can be accuser and witness; that evidence is not taken 'on oath of calumny,' since it is a quasi-spiritual lawsuit; that relatives are allowed as witnesses; that the juridical order is not perfectly observed, since if the denunciation has been made, and the suit is uncontested, the defendant may be excommunicated if contumacious; that hearsay evidence is admitted; and that witnesses may be called after the publication of the names of the witnesses." All this is in order to prevent the sin that may occur in such a union (cap. Quoties aliqui; cap. Super eo, De test. et attest.; cap. Literas, De juram. calumn.).

This suffices for the Replies to the Objections.