Some Questions regarding Human Generation

by John Ziegler


The human act

A human act means one that is human essentially: not merely an act that happens to be done by a human, like losing one's balance, but one done deliberately, which is to say freely and knowingly. Although 'free' means without coercion, it does not mean without any restraint at all. What we call the moral 'ought' is a bond which binds the free, exactly as it is free: the proper bond of the free, to put it as a sort of paradox. That is, one is bound to use freedom well: one is bound (in one order) to use freedom (in another order) as befits a rational being. Towards what, since what is done is done for an end? Towards that end which is reasonable: in accord with reason, with what reason knows to be suitable for a rational animal (even before, as it were, considering man's supernatural ordination, and what is suitable for that).

Morality of the human act

This general requirement, reasonableness, as source of the morality of a human act means that we need to examine the character of each act, to determine how it measures up to that requirement. The morality of a human act is measured by three measures. To begin to understand this, let us for a moment consider that there is this fundamental point about any right, such as the right to one's own goods: that exercise of a right does not of itself render the exercise morally right. I have the right to use my carving knife, but it is not morally right to use it to kill Aunt Molly. What the right does is to remove one evil, one malice, from an act; even so, in killing Aunt Molly with my own knife I am not thieving the knife. To be morally right, my act must also be free of that other malice of homicide. English is deficient here, in that the word 'right' is used in two senses. In Latin there is 'jus', meaning a right such as the right to use; and there is 'rectus', meaning 'morally right' or 'upright', without moral defect (we say 'right' or 'all right' in that sense). To be morally good, an act must be 'rectus'; 'jus' merely removes one malice: 'rectus' means without any malice at all. Goodness, as St Thomas observes, comes from integrity of causes, but evil from any defect. An act, in common with any being, is good as a being, and is of greater good according as it is of greater being: evil (physical or moral) is a defect. To say that a human act is morally measured by three measures is to say that there are three sources of its moral being, and three possible avenues of moral defect.

Now first, the nature of any act is taken from its object, what the act necessarily is. Every act is the attaining of something, as the act of the fire in heating water is an act of heating in that heat is attained. This is natural to any act, meaning that it is the nature of the act. We say that an act has a natural end, as an action of heating has as its natural end the attaining of heat. As such, it is independent of what I might intend, as if I apply the fire to the water simply to test whether the gas-jet is working. So it is with a human act, as regards its morality. Thus, the unjust taking of another's life is always murder, and remains unjust, regardless of whether I might perform the murder for a political purpose. It might then be called a political murder, but it remains murder. If one were to murder intending good, such as the saving of someone's (someone else's, obviously) life, the murder is not thereby good, for it remains that murder is bad. A goodness in intention does not remove a badness in the nature of the act.

Secondly, whilst there are acts like murder which are always wrong from their object, which necessarily includes wrongness, there are acts which are not bad from their object. Some are good from their object, such as telling the truth; and some are morally indifferent from their object. Thus, walking is morally indifferent from its nature. In a case of indifference from object, the morality comes from what is accidental to the act, what is beyond its nature but belonging to it. Now, every human act necessarily proceeds from a purpose, an end intended (whether explicitly or implicitly). This is necessary although an accident of every such act (because it is other than what it is), and always therefore attaches morality. For the rest, other circumstances may or may not import morality: thus, an act of eating is not morally affected by the circumstance that it is done on any Wednesday; but it is if on a Wednesday I eat very well without good reason, under circumstances which leave others deprived.

Thus, removing someone's property, given the circumstance that I do it against his reasonable will, makes my act theft. Or again, an act of walking from its nature is indifferent morally; but if a circumstance of the walking is that it happens to be done on a newly planted lawn, then the walking becomes a destructive act. Even that leaves it morally indifferent: thus, if I walk thus intending injustice to someone through the destruction, then the act is bad; but were I to do it in rescuing a child from a menacing dog then I am not to be blamed but praised. That is to say that the morality of a human act, if indifferent by reason of its object - neither morally required nor morally prohibited - is taken from its purpose, if not determined from other circumstance.

In any case, the intention from which an act is done can make an indifferent act bad, but cannot make good an act bad by nature; for that would simply be to do evil. The end always justifies the means - of course, nothing but the end can ever justify any means. But, that is not at all to be confused with this: evil may not be done, even though good come of it. A lie, told for whatever good motive, remains wrong, for it perverts the very end of speech. So-called pious lies are still lies. A good motive does not christen a bad act.

What are we to say about an act, good by nature, such as telling the truth, done for a bad purpose, such as unreasonably destroying someone's good name? There is, after all, such a thing as malicious truth-telling. A bad motive means a bad act.

Notion of the natural

The natural is what is given. This does not only refer to birds, trees and small furry animals: as though any contact with art somehow neutralizes the natural. Aristotle had remarked that the way to determine if something is natural is first to ask whether its principle of activity is intrinsic to it. For each thing is for the sake of its operation, or, rather, is for the sake of itself operating. To know what constitutes something is indeed valuable: thus, in geometry we know what constitutes triangle. However, knowledge like that of the mathematician leaves us in ignorance of activity. Indeed, for all that mathematics enlightens various sciences, through it we learn nothing of that vast network of the proper activities of things. One has not grasped the reality, the nature, of things without knowing, or at least co-knowing, these activities. Thus, the principle of activity of a motor car is the order of its parts which is imposed by the designer, although underlying that artificial activity, what is natural, is the intrinsic character and properties and proper activities of the metals etc. from which the parts are made and assembled. Or again, I might make use of what is otherwise natural for an end I impose upon it, as a farmer does. Now, every act of anything whatsoever is always the attaining of something, as has been said: so that every act has this as its nature, regardless of a further end I may impose upon it; as testing the gas-jet is an artificial end added to the natural end of heating by the fire.

This given character of the natural, which is obvious to a child not less than to a mature mind, and is fundamental to Aristotle and Aquinas, has been devalued in recent philosophy. It is not so much that mankind has increased his skill in art, technology. It is not that we live more surrounded by artifacts than did the Greeks or the Mediaevals, and are consequently less reminded of the natural than they: for there are natural things in the human psyche which art does not alter - the love of friendship, the pain of loss. And man the artist - anyone who has ever made anything - knows how obstinately resistive to his will are his materials. Nor is it that recent history shows us increasingly imposing our will on what is given. It is rather a matter of value. And the valuation is the result of a restriction in insight. Where St Thomas saw that human soul and body constitute one thing, Descartes says they are two. The very same illustration, that of a pilot (the soul) and his ship (the body) which St Thomas gives specifically to insist that it is not an illustration of the relation between soul and body, Descartes, who had never read him, gives specifically to illustrate that it is. For Aristotle and Aquinas, the realists, what is human is the animated human body. For Descartes, and in this theme he has been followed in their various ways by many philosophers, the body is at the disposal of the soul. Indeed, it was Plato who declared that the body is unto the harm of the soul; Aristotle corrected him by contradicting him, showing that the body must be unto the good of the soul, and in this he is reinforced by Aquinas. Now this devaluing of the naturalness of the human body by prevailing philosophies has found its way from them into many minds. In our day, many who would think it wrong to allow a species of plant to become extinct in 'nature', or that human activity should threaten the natural habitat of an animal, do not think it wrong to intervene arbitrarily in the natural processes of human life.

At this point it would be useful to consider the natural taken comparatively to the artificial and to the violent. Both of the latter are opposed, but in different ways, to the natural. Thus, what is natural comes from a principle in the thing in question (as also does what is voluntary), whereas the notion of both the artificial and the violent is that they are imposed from without. But whereas what is properly artificial does not oppose nature (on the contrary, it adds something), the violent is always opposed to the natural (for it destroys by subtracting something). So it is that clothes-wearing is artificial, and in accord with nature; whereas de-educating someone is not natural, but violent. What constitutes violence in the moral order is to prefer the lesser good to the greater, thereby destroying due order in the human act, and is for that reason wrong. Violence is not solely the province of the thug. And what of the act of the butcher who kills the sheep for food? Or, for that matter, of the gardener or the cook who kills the carrot for food? From the point of view of the sheep or the carrot it is undoubtedly violent, but from the point of view of the superior principle that the lower is for the sake of the higher, it is an act of art.


Vital generation is defined by St Thomas as the origin of a living substance from a conjoined living principle unto similitude of nature.

First, generation in general (to include non vital generation) is the origin of something in a real subject. Thus, for instance, water is generated from oxygen and hydrogen. In this case there arises a new substance (wherein substantial generation differs from accidental generation, where a new accident, heat for example, arises in a subject such as steel). But substantial generation may be either non vital as in the example, or vital, generation as found in living things. Secondly, in vital generation there is found something peculiar to the living: for vital generation is not merely accidentally vital, as if it differed only from non vital generation merely in that the generation happened to concern something living (as, say, falling from a height involving a dog differs from that involving a brick only in that the faller happens to be alive). Rather, vital generation is properly vital. What this means is that, since the proper distinctive of the living is that it perfects itself - in common with the non living, living bodies act towards entropy, but what is proper to them is that they continually reestablish those tensions in virtue of which they can act towards entropy - we find self perfection in vital generation. That is to say, vital generation is a strictly vital, a self-perfective operation. As such, we find in it the following characters:

Thus, that definition of St Thomas sums up those characteristics.

Human generation

Human generation, however, has more to it than that: it is both generation and specifically human.

First, freedom being involved, it has morality. There is pleasure in the sexual act, and sensual pleasure has this moral characteristic: that it is pursuable for itself in a way that something without pleasure, like nasty medicine, is not; and at the same time it is not suitable for a rational animal as an end to which to subordinate all action. If it is to be pursued - and the fact that there is pleasure in the act is a sign that it is naturally good - then there needs to be a more elevated end to render it fit to pursue. The natural end is a new person, and this certainly renders it fit to pursue. But this need not be its explicit purpose, provided that one at least accept that natural end within one's purposed end. This means that one may not, in the order of intention, detach the natural end from the pleasure by positively intending to block the natural culmination while accepting the pleasure.

Secondly, the generated is a person, that which is most perfect in all of nature, and which is itself an end and is morally incapable of being a means. (Indeed, the person, as person, as possessed of intellect and will, is simply incapable of being a means at all. If I bend someone to my will so as to do my bidding, he is at the same time, in the grandiloquent old phrase, captain of his soul, and does his bidding.) The person is an end. The person therefore has rights which may not be subordinated; thus I may not put the life or substantial well-being of a person in proximate risk (although remote risk to life, limb, or property is inherent in any physical activity). Thus, I may not drive in a manner dangerous to people. Similarly, I may not fire a rifle in a direction that is probably deserted, because it is certain that anyone who might be there has the right that I abstain; I would need to make sure first.

Thirdly, in common with sexual generation commonly, it is social. It is a process which by its very tendency is productive of a new human. The fact that the very reproductive character of the process is sexual, digenesis rather than monogenesis in the fashion of lower life forms, means that it is social: it requires a society, the conjugal society, and not merely for fertilisation. The human conjugal society requires to have stability for the task of rearing and educating offspring - offspring at first indigent and ignorant and far from perfection, and in need of social help, and that indeed for many years. Because human generation is social, in inception as well as in continuation, and because the social aspect, as part of generation itself, is for the sake of the person, then it offends against the integrity of human generation to aim to separate the social aspect from the generative. Thus divorce, parental neglect, fornication, rape, all offend against the social aspect of human generation - I do not say it is their only offence - divorce and parental neglect posteriorly to fertilisation, fornication and rape anteriorly. Similarly to be judged is the 'constructive' neglect of choosing single parenthood, or of forcing it by desertion. One might object that rules should admit exceptions, and that divorce, for example, might be far the most convenient solution for a particular dispute. Whilst that may be true in a given case, it is naturally necessary that prohibition of divorce be universal since there is no principle by which it should apply to some rather than others; and we see about us the devastation to persons from laxity in this regard.

Generation is natural, although indeed at the disposal of will as to its inception - but not as to its course, which is quite independent of will in its natural, its given, character. It is independent of will, except that will can bring about physical intervention, which must therefore be either art or violence, and that involving that specifically human thing, the human body and what is natural to it. In the case of something natural, but sub-human, interference can indeed be arbitrary, as happens in gratuitous cruelty, but otherwise is justified by some benefit to flow to man, such as happens with research using animals, or killing them for food or even for recreation. But in the case of something natural which is human, intervention can only be justified by a reason that acknowledges that the action is done not only by, but upon, a person. Neither is it a matter of consent of the person involved (although one does not hear of seeking consent of the person who is the subject of abortion). I do not have the right to destroy or to damage even my own body, for as St Thomas points out, each thing loves naturally its own being, so that to will otherwise is contrary to the inclination of nature, and therefore violent. The medical art is an art which cooperates with nature, in the very real sense that it is impossible without nature: but also in the very real sense that should it try to operate contrary to nature it is then skill, if you like, but skill which is violence rather than art.


We may now turn to questions of operation upon human generation. To operate upon need not be to interfere, if by interference we mean some action taken to deflect some part of the natural process: thus, operations like ultrasonic inspection of an embryo would not be interference in this sense, although abortion clearly is. Now whilst an action to deflect may indeed be done for the purpose of adding something (some benefit to a person), the nature of deflection is precisely to subtract by substitution of another goal. If the goal deflected from is something of a person in the sense that it is part of the process of generation of a person, this places the action in the category of the violent. And this is true whether the goal be proximate, achievement of this part of the process of generation, or remote, a person newly born, or still more remote, a person nurtured and educated. On the other hand, if there were per accidens a defect in the natural process in a given case, then operation to restore the natural would not be deflection but restoration. It would not be violence but genuinely art.

Certain practices such as abortion and contraception are wrong by nature. Others, however, are not wrong by nature but amount to interference and therefore violence unless done by way of restoration. There is no natural right to interfere.


Abortion, from the nature of the act, is obviously violence directly against the person. This is in no way changed by casting doubt on whether, or when, a human embryo is genuinely human. From what we saw before, I may not act to destroy a human embryo or fertilised ovum on the probability that it is not a person. Indeed, it seems that the opposite opinion is to be held. Discoveries of recent years in genetics and embryology greatly increase the evidence that the person exists from the moment of fertilisation. We now know that development towards organisation which can support an intellect is governed by a principle intrinsic to the very fertilised ovum from the start.

Artificial Insemination

The practice of contraception was for a time referred to as 'artificial birth control', by which term it was contrasted with intentional periodic abstinence which was called 'natural birth control'. It should be quite clear that neither of these terms is, properly speaking, correct. Contraception, meaning accepting the pleasure but rejecting the fertilisation, is properly called violent; and periodic abstinence is in the strict sense artificial rather than natural. If artificial insemination were indeed artificial, it would not be wrong. But what is called artificial insemination usually involves doing violence to the human generative act in its social aspect. If as practised it involves obtaining germ cells other than through marital intercourse, then it involves violence and is wrong for that. If art were used to rectify some impediment to fertilisation, given marital intercourse, then 'artificial insemination' would be truly artificial and licit; but not otherwise. If one were to object that this seems to remove benefits from disabled people, then I would reply that human art can be very ingenious (the words 'engineer' and 'ingenious' are the same) but that there must be some level of disability which renders it impossible for someone to be a parent: and that one may not do evil that good may come of it.

In vitro fertilisation

It is similar with fertilisation in vitro. As with 'artificial insemination', which is similar in this respect, it is violent rather than artificial if not done in the context of marital intercourse. It is obvious moreover that any practices which might be associated with it involving fertilisation of many ova and then rejection of some of these fertilised ova would be violence against the person, having the same morality as abortion. In addition, it is wrong not by the fact that it is in vitro rather than in vivo, as if location in itself were important, but because of interference in the natural process of fertilisation, unless it were restorative.

Surrogate Motherhood

In itself, surrogate motherhood is the nurturing of a human embryo in the uterus of one who is not the mother. Because it is nurturing, it is not by reason of its nature wrong: but neither is it the object of a natural right. Its morality remains to be determined by the circumstances if its purpose is good: but if done by way of interference, that circumstance renders it violent.

Suppose the mother died, and in an effort to save the embryo it were transplanted into another's uterus under conditions conducing to continuation of gestation. This, given the nature of the act as indifferent, and, as was just said, a good purpose and circumstance that it is done by way of restoration, would mean a morally good act. However, this is not what happens in cases of surrogate motherhood. To avoid the technological difficulty of explanting from the mother's uterus, it is usually done preceded by fertilisation other than through marital intercourse, entailing morally wrong action for that reason.

Secondly, notionally it might be done (although I do not know whether it is at present possible) by explanting from the mother thereby avoiding moral violence regarding fertilisation. In such a case one would assume there to be some medical risk to the embryo, or for that matter to the mother or surrogate mother, in the transplantation involved. One might then licitly undertake to take that risk given a weighty reason, such as proximate risk to mother or embryo should it not be done. However, in common with medical procedures involving risk, a remote risk, such as that the mother might develop a dangerous condition, would not seem to justify it since it would replace a remote risk with a similar but proximate one due to the surgery.

Thirdly, even if there were no surgical risk, surrogate motherhood would be interference in the natural process, and therefore unjustified, unless it were by way of restoration.

John Ziegler

John Ziegler is a lecturer at the Centre for Thomistic Studies, in Sydney, Australia.

This article posted December 1997. It was published in Universitas, Vol 1 (1997), No. 2.
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