In the present case, the Judges in first instance, holding the Petitioner incapable of assuming the essential obligations of marriage, took as their measure "the care and concern essential to build up a normal and human marriage relationship" (Acts, 99). But there seems to be no way by which one can establish a working juridic criterion to judge the "normality" of a marriage relationship. As a result of Original Sin, the relationship between husband and wife will always tend in some way to diverge from the harmony which the covenant of conjugal love morally calls for. In the first state of creation, perfect harmony between man and woman was no doubt achieved without effort. But, after the Fall, " The harmony in which they had found themselves, thanks to original justice, is now destroyed: the control of the soul's spiritual faculties over the body is shattered; the union of man and woman becomes subject to tensions, their relations henceforth marked by lust and domination" (CCC 400). Only those couples who are prepared to make a sustained effort and who at the same time count on the help of grace are likely to achieve a close and serene relationship. It follows that however regrettable and however morally imputable (to one or both parties) marital discord may be, some measure of it is common and simply a sign of human imperfection.
Even in cases where the discord has become serious (as usually happens before conjugal life definitively breaks down), this of itself offers no proof of consensual incapacity. A marital breakdown can always be considered as a pathological event; yet it does not necessarily follow that there was anything pathological in the consent to marriage originally given. The pathology ending in the breakdown often derives not from some original constitutional incapacity but from the subsequent voluntary refusal of one or both spouses to make the effort needed to learn to get on. "Il fallimento dell'unione coniugale, peraltro, non è mai in sé una prova per dimostrare tale incapacità dei contraenti, i quali possono aver trascurato, o usato male, i mezzi sia naturali che soprannaturali a loro disposizione..." (AAS (1987) 1457)
The first Sentence holds that the "ability to adjust to each other [is] an essential for marriage" (I, 100). While this is no doubt true from the viewpoint of ideal peace in actual conjugal life, it is a moral requisite of a successful marriage, not a juridic condition for the capacity to consent to the conjugal relationship, thus instituting the marital bond. Canon 1095, 2 and 3 specifically correlate consensual incapacity to the essential obligations of marriage in themselves, not to the person of the other spouse. This is quite clear and explains why rotal jurisprudence, despite one or two divergent voices, has constantly and solidly rejected the notion of "relative incapacity". *
Adjustment to one another over a lifetime is always a difficult requirement of the married covenant. However one can see no way by which the law could judge with moral certainty that the deteriorated relationship of two spouses derived from an original and constitutional incapacity to get on - somehow attributable to the two of them - , and not from the simple moral failure, of one or the other or both, to measure up to the normal effort needed to adjust in married life.
Certainly if some grave personality disorder in one or other of the spouses was present at the moment of the wedding, it is very likely to provoke maladjustment between them. But the maladjustment does not prove the disorder. Moreover even if the disorder is proved, it is irrelevant to argue that it tended to create maladjustment between the spouses, for this can be readily admitted. What must be proved is that it actually incapacitated for marital consent itself. "Ability to adjust to one's partner" is not qualifiable or quantifiable in law and cannot be ranged among the constitutional obligations of which the measure must be taken, under c. 1095, in order to judge consensual capacity or incapacity.
In coming to its affirmative decision, the first instance Judges were swayed by the argument that the parties "could not manage contradictory life styles" (100). If such an argument is accepted as conclusive, then any serious difficulty in getting on becomes proof of incapacity. It is hard to see how such "post hoc, ergo propter hoc" reasoning does not in effect canonize divorce. If a couple manage to get on, then their union is valid. If they fail to do so, then the marriage can be declared null because of an incapacity held to be demonstrated by their failure.
Gaudium et Spes expresses the highly personalist idea of marriage as involving a "mutuum sui ipsius donum" (GS 49). In the post-conciliar renewal of church law, this led to the strikingly new canonical description of marital consent offered by the 1983 Code: the "act of the will by which a man and a woman, through an irrevocable covenant, mutually give and accept each other..." (c. 1057, § 2). Thus each spouse is the object of the spousal self-donation of the other. Each one, in this mutual donation, not only has the right to receive the self-gift of the other, but also the duty to accept it. Consent therefore involves a marital giving of one's real self as one is, and a marital acceptance of the real self of the other, as he or she too actually is - not as one would like him or her to be. Neither party has the right that the other be as one thinks or wants; or that (barring cases of deceit: cf. c. 1098) he or she be endowed with certain positive qualities or free from other negative ones.
Moreover, the possibility that one can be mistaken in one's assessment of another is to be counted among the normal psychological limitations of every person, and therefore also of those who marry. Consequently, it affords no sign or proof of consensual incapacity. Many people are poor psychological judges of others; yet they certainly cannot on that account be declared incapable of exercising the basis human and ecclesial right to marry (cfr. c. 1058).
It is evident that common defects cannot offer reasonable grounds for declaring a person incapable of giving valid marital consent. Bad temper is not uncommon. A tendency to violence is less common and certainly more serious. Yet it cannot justify the conclusion that a person was consensually incapable under c. 1095, 3º, unless it is shown to have been so serious, so rooted in the person at the time of the wedding, and so beyond his or her power to control, as to necessarily reveal a personality that was gravely and constitutionally anomalous.