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Coeli beatus: Observations of a biologist


Jerôme Lejeune

Pontifical Academy of Sciences




We are the only species on earth to wonder who we are and where we are going, and on occasion to ask ourselves the fearsome questions: «How is it with your brother?»; «What have you done with your child?»


The elementary impulses concerned with perpetuating the species are present in all living beings, but we are the only ones who know about the mysterious relationship between love and the future. Neither the cleverest nor the best trained of chimpanzees could ever conceive there was any relationship between his mounting his female and the arrival nine months later of a baby looking just like him.


We for our part have always known that sexual appetite and its pleasurable satisfaction are by their nature linked to procreation. Didn’t the ancients, poetically and absolutely realistically, represent the passion of love with the features of a child?



Human nature


Today all of us know very well that human nature no longer exists. Our impulses and actions, especially in the sexual sphere, are no more than mere conventions imposed by society and varying according to the times. As the neo-humanists have now formally decreed, there is no biological law to guide or enlighten us.


Given that the scientific spirit does not accept sweeping statements without benefit of supporting evidence, we may be permitted to think twice before accepting that the instincts of our species do not exist or that the amorous impulses are only meaningless, illogical tremors. Neuroanatomy shows us how rash it would be to disregard how we are made. The ‘skin sack’ which covers and defines this house of flesh in which we dwell is replicated point by point in the cerebral cortex. At about the height of the head-band which girls sometimes use to keep their hair in place, on the posterior slope of the fissure of Rolando, a sensory representation of our entire body may be observed.


The neurological homunculus1 is as it were. stretched out on the ascending parietal, its head turned downwards, the legs upwards, with the feet dangling in the furrow separating the two hemispheres. The parts are all to be found in the normal order: head, neck, hand, arm, trunk, pelvis, leg, foot and toes and, below the toes, the genital organs. This arrangement, surprising at first sight, is absolutely logical once we remember we walk upright. If we went on all fours, we should see that the genital organ would be in effect at the posterior extremity of the trunk and would consequently be projected immediately after the representation of the leg and toes.


Thus the genital sphere is the only part of our body, the cerebral representation of which comes into direct contact with the enormous limbic lobe, the seat of all the emotions. For it is in this last that the impulses are organized that move us: those which have to do with the survival of the individual (hunger, thirst, aggression) and those concerned with the continuation of the species (genital appetite, attraction to a partner, protection of the young, loyalty to one’s own kind).


From this it follows that we are so made that what involves the sphere directly disturbs morality from a neurological point of view. Hence the impossibility (it would seem) of curbing emotional behaviour and controlling the instincts, if the empire of the will does not extend to, and perhaps especially to, conscious and deliberate genital behaviour.


The old witticism of the cynical in days gone by, «If morality exists, it’s a pity it’s sited in one’s pants», only showed ignorance of neuro-anatomy. The rigorists were certainly not mistaken in siting the genital organ in close contact with the emotions: it was memory of life.



Fontes vitae


From time to time all through life, the amorous impulses make themselves felt, whether in isolation or all at once, and it is the individual’s job to hold them in balance. Being a particularly powerful impulse, the genital appetite can manifest itself in complete isolation in the lowest orders of living creatures. Certain male fish, for instance, scatter their sperm over eggs laid by a female they do not know and will never meet. If reduced to the genital impulse, sexual behaviour would be satisfied with a mere automatic discharge.


In higher creatures, attraction to the opposite sex directs this appetite and, in us, tenderness completes its meaning: the union of two people is needed to generate a third. This typical trilogy of natural reproduction2 requires that affection unite persons of differing sex. Whence the expression in common usage, regarding the homosexual relationship as against nature in that it satisfies the appetite in a counterfeit way3 and can in no way respect the partner, much less the child.


The transmission of life is not exhausted in procreation: the protection of the young represents the obligatory sequel to it. This impulse is so strong in all vertebrates (and even in invertebrates), there seems a need to insist on its importance for us human beings. At the newborn child’s first cry, anyone can feel the tug of this irresistible call. Abortion and infanticide,4 however, show how terribly human nature can be distorted.


Lastly, loyalty to the family and the group, this feeling of belonging, this need to give oneself totally, comprises the basis of society. The abandoning of babies, however, or doing away with the sick (as certain trend-setters, tirelessly dusting off the most ancient sophisms, recommend) show how vulnerable these instincts are in our species.5


The natural sciences, however, are in no position to take us any further. While not abandoning hope of a deeper analysis, the biologist prudently and respectfully observes this exquisitely human phenomenon of the commitment of persons:

— leaving father and mother in order to form one flesh forever with a spouse of one’s own may be easy to imagine;

— protecting one’s children, parents and all members of one’s group seems just what one should hope for;

— giving up one’s life for those whom one loves, this too is conceivable, at least in theory.


Without pretending to ignore the difficulties and sufferings or simply the inconveniences of marriage, it is obvious it gives equilibrium to loving relationships. So why reject the humble joys of the hearth, the charm of children, the warmth of family and group? Why this voluntary forsaking of these guaranteed forms of happiness? No inclination predisposes us in this direction. This notwithstanding, consecrated celibacy clearly shows that another kind of equilibrium is possible.





The thought processes of a biologist cannot hope to explain a religious phenomenon; they are, however, able to study its more obvious effects. The feeling of belonging can find its highest form of development in celibacy. These words of an experienced missionary bear witness to the fact. «In all my career,» he said, «and in the most godforsaken places, I have never encountered strangers. Wherever I’ve been, I’ve found brothers and sisters.»


For seen from heaven, if one may use such an expression, the view is wider. The priest recognizes one of his own kind in his neighbour, but at the same time feels, in the brother or sister, he sees the spirit of the Father, whom he does not see. Human nature is a distorting mirror, scratched and blistered by the scar of our original sin, our intellect divided between reason and heart. But this uncertain likeness, this indistinct image, almost unrecognizable indeed, can nonetheless be perceived by him whose eye is changed.


Protection of the little ones can also be exercised to the full. A brilliant Christian intuition has been to associate the virtue of goodness to the parental character.


Women who serve the poorest, the marginalized, the little loved, are rightly known as ‘sisters’ and more rightly still as ‘good’. More than any sociological or statistical parameter, the role of the good sisters is the empirical measure of the degree of Christianity. A detail of dress is helpful to them in their work. The veil is extremely useful in that it prevents the affection shown and the charity lavished from being subjected to false interpretations. A little sister of the infirm observed that, dressed as well as possible, as is the case today, she no longer dared to enter shady neighbourhoods with the same confidence as before. «The people», she said, «can no longer tell in whose name I am coming.» This was how she expressed her personal commitment: the sole reason for celibacy. And this is how a superior gave me to understand it, as she guided her convent with most effective sweetness: «Commitment, choosing the bridegroom, yes, we’re talking about vocation. It is said that priests and nuns must not get married, so as to be fully available to consecrate themselves to God and devote themselves to other people.

—Of course, this is perfectly true, but the truth lies the other way around: when one is fully committed to God, how can one contract a second marriage?

—To our postulants, I answer: If you don’t feel called to follow the Lord as one of his companions, go and find yourself a husband. Both vocations are OK, but not both at once!»

This leaves the genital appetite, our most insistent and explosive of impulses, at least on the physical level. However fundamental it may be (and on it depends the future of the species), this biological function is the only one that does not produce a pathological condition if left unsatisfied. One cannot say the same for hunger, thirst or the need for sleep.


In celibacy the impulse persists, always just as specialized, yet the appetite gradually becomes generalized. From having been genital, it grows ingeniously back up the tree of life to him who begat it. By seeking our happiness on the other slope of time, the human being, healed at last, is united to the infinite Present.


This appetite for the sublime is perhaps the origin of the word coelibatus. Seneca used it for the unmarried state. Julius Valerianus applied it to the life celestial. This little known historian had perhaps come closer to the truth than distinguished moralists: the heart that renounces earthly loves for the greatest love of all is indeed Coeli beatus.





I. More accurately, one ought to speak of the semi-homunculus, given that the right side is projected on the left side of the brain and vice-versa, and the human figure is upside down and set cross-wise. Another detail: the head is separated from the trunk, as though held between the fingers. The neuronal man, in effect, does not have a head on his shoulders. Here too, typology unveils the mystery: this arrangement permits the simplest possible wiring system to project on a flat surface each point of a sphere linked with a cylinder, the head mounted on the neck.

2. This is to say: when the conjunction of the gametes is the result of the union of the persons and not of the act of a third agent, as in the case of in vitro fertilization or of artificial insemination by syringe.

3. Our own age knows all too well what devastation has been wrought by sodomy. The AIDS epidemic is a fearful example of this. We are not talking in terms of a punishment, of course, but merely of the result of acting against nature. God alone can forgive those who break his laws; human beings forgive only rarely; nature never does, not being a person.

4. Abortion and infanticide are abominable crimes (Vatican II, Gaudium et spes, 51).

5. For each of these cases, analogies may be found throughout the animal kingdom. Among the higher animals, one may cite examples which, although isolated, are extremely striking, and which are indeed pretty instructive, for all that the mechanism that triggers them off is unconscious.