The Roman Catholic magisterium infallibly teaches (under the ordinary and universal Magisterium) that the morality of each and every human act depends only on three things:
(1) intention — the end intended by the person who acts; in other words, the purpose for choosing the act.
(2) moral object — the end toward which the knowingly chosen act is inherently ordered
(3) circumstances — the reasonably anticipated good and bad end results (consequences) of the act
Each font proceeds from the human will, but toward different ends. Each font has its morality determined by that end.
In this post, I’ll explain the second font of morality, the moral object of the chosen act, in terms of its basic structure.
The Basic Structure
Speaking only of the second font, the structure in every case is the same:
a. The free will chooses
b. the act itself
c. with its essential moral nature
d. as determined by its object.
These four components and their relationship determine if an act is intrinsically evil or not: a choice, the act itself, its nature, and its object. Let’s examine each in detail, along with the varied wording used to describe these components of the human act.
a. The free will chooses
A knowing choice by the free will is at the heart of every human act, of every act subject to the moral law. If a person seems to act, yet they do so entirely without free will, there can be no sin because there is no “human act”, no act subject to morality.
Now this principle in no way exempts persons acting under duress from the moral law. The reason it is called “duress” is that a threat or difficult circumstance weighs upon the free will. Duress may reduce the ability of the free will to act with full deliberation, thereby reducing culpability. Duress may compromise the understanding of the morality of the act by the intellect, thereby reducing culpability. But the simple fact that duress exists does not exempt the conscience from the moral law.
 cf. Decree of the Holy Office, 4 March 1679, n. 51; Denzinger, n. 1201, and See my explanation in Conte, Catechism of Catholic Ethics, n. 439.
On the other hand, severe mental illness, severe mental disability, or the normal lack of development found in any infant or toddler are all examples of human persons who either lack the use of reason and free will, or at least do not have sufficient use to knowingly and freely commit a mortal sin. But for most of humanity, the ability to know and to freely choose implies the possibility of sin, even grave sin.
The choice of the free will must always be a knowing choice. The person must know what type of act he is choosing. He might dispute with the Church or with his conscience as to whether or not that act is moral. But in order for the moral law to apply to the act, he must know its type.
For example, a man freely chooses to have a nice salad for dinner. Unknown to him, the salad contains some poisonous mushrooms. He eats the meal and unfortunately dies. His act is not the actual mortal sin of suicide, because he certainly lacks full knowledge and full deliberation. But was his act, on a merely objective level, the intrinsically evil act of suicide? No, it was not. For he did not know that in choosing the meal, he was choosing his own death. His choice was in no sense a sin or an intrinsically evil act.
In another example, if a physician knowingly chooses to give an overdose of a pain killer (e.g. morphine) to a terminally ill patient, the act is euthanasia (a type of murder). But if he gives what he reasonably believes to be a suitable dose for that patient, to relieve suffering without killing, death might result anyway. Terminally ill patients are in a weakened state, so it is difficult to determine how much morphine they can tolerate. In this latter case, he did not knowingly choose an act ordered toward the death of an innocent, so his act was not intrinsically evil.
The first part of the second font is a choice of the free will. That choice can be termed “knowing”, since the person must know the type of act he is choosing. The choice can also be termed “deliberate” or “intentional”, since the person chooses freely. The morality of human acts is based on the knowing choices of reason and free will.
However, a person’s judgment as to whether a type of act is a sin is another matter. Consider a man who is terminally ill, and who knowingly chooses to commit suicide. His death is not accidental; it is deliberate. His conscience (let’s say, as a non-Catholic) might sincerely but mistakenly believe that suicide is moral in dire circumstances. Yet his knowingly chosen act is intrinsically evil; it is objectively the mortal sin of suicide. The act is not an actual mortal sin, as he lacks the full knowledge required: he does not know that suicide is always gravely immoral. Perhaps his suffering and anguish also weigh upon his free will, reducing the culpability of his deliberation. But regardless of these factors, he has sufficient knowledge for his choice to be objectively an intrinsically evil act. He knows the type of act he is choosing.
This choice of the free will can be termed: knowing, intentional, deliberate, voluntary, or any similar phrasing. The moral choices of the human person are of the intellect, which knows, and of the free will, which chooses. So it is indispensable that the choice of the act itself be knowing and intentional (deliberate, voluntary). An act subject to morality is always a knowing intentional choice.
This requirement of a knowing free choice applies whether the act itself is intrinsically evil or intrinsically good. It applies regardless of whether the act is objectively moral or immoral. It applies regardless of whether the sin is venial or mortal in culpability. Even when the act is objectively sinful, yet the person acts with a sincerely mistaken conscience, the choice is of the intellect and free will; it is a knowing free choice — or else it is not an “act”.
b. the act itself
The human person knowingly chooses the act itself. In Veritatis Splendor, the concept of the act itself is expressed using various terms, including: “concrete actions,” “concrete acts,” “particular acts,” and “specific acts”. The act has a moral nature, but it also takes a concrete or particular form in any case.
Suppose I tell you that my neighbor committed an act of theft. You then ask me: “What did he steal?” and “How did he steal it?” The answers to these questions describe the act itself: a particular example of some kind of behavior. Theft is the nature of the act. But every human act is a particular expression of a general type of act. The type of the act, in terms of morality, is also termed its kind, genus, species, or nature. But for any type of act to occur as an act of a human person, it must take a concrete or particular form in the case at hand.
What does the human person intentionally choose in the second font? He chooses the act itself, a particular concrete action or behavior. There are many ways to commit theft and many items that might be stolen; these are the particular acts (the act itself). But every such particular or concrete act of theft is still properly called theft, despite all the differences in each case. Theft is the nature of the act; it is the general classification of the act in terms of morality. The act itself is a specific example of a general type.
What does the human person choose? In the first font, the person chooses an intended end, which is the goal sought by the person by means of the action. This goal motivates the person to act. But in the second font, the person chooses the particular act itself. The use of the terms “intentional” or “deliberate” or “voluntary” in describing intrinsically evil acts refer to the choice of the act itself by the free will. But the choice of any particular act necessarily includes its nature and its object.
No one can directly choose a moral object. The object of the act is an end toward which the particular act is inherently ordered. This ordering of the act itself toward an end constitutes its moral type. But the person cannot choose the nature or the object of the act directly; he can only choose the concrete act. The nature and object are inherent to that chosen particular act.
If you wish to choose a particular moral object, you must choose an act inherently ordered to that end. If you choose an act inherently ordered toward that end, you are in fact necessarily also choosing that object, at least implicitly. And this choice is intentional; it is a knowing and deliberate exercise of reason and free will. Whoever says otherwise, denies the objective morality of human acts.
In euthanasia, the intended end is to relieve the suffering of the patient, but the chosen act is ordered toward killing an innocent person. The act itself, in any case of euthanasia, is the particular chosen action, such as deliberately giving the patient a known overdose of morphine. The intention to relieve suffering does not change the chosen act itself, its nature, or its object. The intentional knowing choice of the concrete act necessarily includes a choice, at least implicitly, of its nature and its object, even when the intended end of the act differs from its object.
In direct abortion to save the life of the mother, the intended end is to save innocent human life, but that is not the moral object. The deliberately chosen act is ordered toward the killing of an innocent prenatal. The particular action is, in one case, a surgical procedure, or, in another case, the taking of an abortifacient drug. But the nature of these acts is found in their ordering toward their object: the killing of an innocent.
Now in this analysis of the constitutive elements of the second font, the choice of the human person is directed toward the act itself, with its nature and its object. The person cannot choose one act and a different object. He cannot somehow will the end of relieving suffering to become the object of the act of killing the innocent. He cannot claim that his will of the intended end, to save the mother’s life, somehow removes the death of the prenatal from the second font. The death of the prenatal is not justified by the claim “unintended side effect” because the intentionally chosen act is ordered toward that end as its moral object. The prenatal is killed directly by the chosen act, making the act intrinsically evil and always gravely immoral.
c. the nature of the act
The human person intentionally and knowingly chooses (in an exercise of will and intellect) a particular concrete act. But all knowingly chosen acts have an inherent moral meaning before the eyes of God. In other words, all the knowing choices of our free will are subject to a “judgment of conscience” and “can be morally evaluated. They are either good or evil.”  There are no morally neutral acts. Every knowingly chosen act has a moral nature.
 Catechism of the Catholic Church, n. 1749.
Every knowing choice of the human person has a moral meaning, a moral nature inherent to the act itself. The nature of the act is its type in terms of morality, also called its “genus” or “species”. This moral meaning or moral nature is inseparable from the chosen particular act (the act itself). The nature of a thing cannot be separated from the thing itself. By choosing any behavior or action, the human person also necessarily chooses, at least implicitly, its moral nature and its moral object. We cannot claim, in choosing to behave a certain way, that the moral meaning of our choice is independent of the chosen concrete act. Every knowing free choice of a specific act has an inherent moral meaning, and the two are inseparable: the act and its inherent moral nature.
One of the more disturbing trends today in moral theology (and in discussions among the faithful) is the search for a reassessment of the basic principles of ethics so that concrete acts will no longer have any particular moral meaning or moral nature inherent to the chosen act. The particular act is said to be “morally neutral” or “morally indifferent” apart from the purpose or intention of the person choosing the act.
In this type of gravely erroneous proposal, the human person imbues the act with a moral meaning by his intent; the physical action itself is claimed to have no essential moral meaning or nature. The object of the act is then said to be derived directly from the will of the person, not from the intrinsic ordering of the chosen act toward its object. Such claims are contrary to the clear and definitive teaching of Veritatis Splendor and the Catechism of the Catholic Church on the three fonts of morality and the moral object.
Acts are termed intrinsically evil precisely because the act is inherently wrong by its very nature. The choice of an intrinsically evil act is an immoral choice of the will. It is not possible to choose such an act, and somehow transform it into a moral choice by intending a good moral object. When you intentionally choose the particular act, you intentionally choose its inherent ordering toward its object, at least implicitly. And that is why intrinsically evil acts are described as morally wrong “in and of themselves” or “by its very nature”.  The will of the human person cannot change or determine the nature of any act. The ordering of the concrete act toward its moral object constitutes its moral nature, and these three are inseparable: act, nature, object.
 Catechism of the Catholic Church, n. 1756, 2485.
d. the object of the act
The moral object determines the inherent moral nature (or “moral species”) of the act itself. When the object is evil, then the act is evil by its very nature. The choice of that act is a choice of its morally disordered nature and its evil end.
Pope Saint John Paul II: “The doctrine of the object as a source of morality represents an authentic explicitation of the Biblical morality of the Covenant and of the commandments, of charity and of the virtues. The moral quality of human acting is dependent on this fidelity to the commandments, as an expression of obedience and of love. For this reason — we repeat — the opinion must be rejected as erroneous which maintains that it is impossible to qualify as morally evil according to its species the deliberate choice of certain kinds of behavior or specific acts, without taking into account the intention for which the choice was made or the totality of the foreseeable consequences of that act for all persons concerned.” 
 Pope John Paul II, Veritatis Splendor, n. 82.
Here “the deliberate choice of certain kinds of behavior” is the second font: the intentional choice of an act with its nature (kind, species, genus, type) as determined by its object. And then the “intention for which the choice was made” is the first font: the intended end or purpose of the act. The “foreseeable consequences of that act for all persons concerned” is the third font: the circumstances.
The term ‘explicitation’ in the Latin text of this document is ‘pate factionem,’ which refers to an explanation that ‘opens’ or ‘makes accessible’ (pate) a truth by ‘division’ into parts (factionem). The three fonts explain morality by dividing it into its constituent elements. When the moral object (second font) of an act is evil, the act itself is intrinsically evil and always immoral, regardless of intention (first font) or consequences (third font). All intrinsically evil acts are defined, in their essential moral nature, solely under the second font.
The act itself is the particular form that any general type of act takes in one case or another; it is the concrete act. The moral nature of that act is also called the type, genus, or species of the act. It is nothing other than the inherent ordering of the act itself toward a proximate end (a morally immediate end), called the moral object. But how do we determine this object of the act? And how do we evaluate its morality?
The object of the act is an end in terms of morality; it is not an act. So for the intrinsically evil act of theft, the object is not “theft”, but rather the deprivation of goods from their owner. Isn’t this type of deprivation theft by definition? Not exactly. This end (object) is what imbues any particular concrete act with the moral nature of theft, but the whole font requires all components: (a) the knowing deliberate choice of (b) the particular act, (c) with its inherent ordering toward (d) that type of deprivation as its object. Its ordering toward that end is its moral nature. But for the act to have the moral nature of theft, all four components are necessary.
The moral object is not any type of end; it is not the intended end, nor the end result. The object is the end toward which the knowingly chosen act is inherently ordered — by the nature of the act itself. However, in some cases the moral object of the act (finis actus) might be the same as the intended end (finis agentis). The Magisterium condemns direct abortion whether the death of the prenatal is the intended end or not.
Pope Saint John Paul II: “The deliberate decision to deprive an innocent human being of his life is always morally evil and can never be licit either as an end in itself or as a means to a good end.” 
 Pope Saint John Paul II, Evangelium Vitae, n. 57.
Abortion is termed a “deliberate decision” because the second font always begins with an intentional knowing choice of a particular act. The act of direct abortion is said to be “an end” when the death of the prenatal is the intended end (first font). Direct abortion is said to be “a means” when the intrinsically evil act of direct abortion (second font) is chosen to attain a different intended end, such as saving the life of the mother. The Magisterium has condemned both abortion and contraception, regardless of whether they are chosen as a means to a good end, or as an end in themselves.  “One may not do evil so that good may result from it.” 
 Pope Paul VI, Humanae Vitae, n. 14.
 Catechism of the Catholic Church, n. 1756.
Since the same end can be in any or all of the three fonts, how do we determine whether an end is the moral object? First of all, the fact that an end is unintended does not prove that it is not also the moral object. The failure to understand this point is a common error in ethics.
In a particular case, someone asserts that the death of the prenatal was “unintended”. If so, then the death is not in the first font; but it might still be the moral object of the second font. The proof of this principle is found in the case of euthanasia, which always by definition includes the good intention to relieve suffering. The death of the innocent suffering person is not the intended end. If it were, the act would not be euthanasia but a different type of murder. So if we begin by determining the intended end, this does not prove which end is the object of the act.
Suppose we then move on to determine the end of the third font, “the totality of the foreseeable consequences of that act for all persons concerned.”  This reasonably anticipated end result of the act determines the morality of the third font. But the death of a prenatal is found in the consequences of both direct abortion and indirect abortion. If the abortion is direct, the death of the prenatal is also the object of the act; if the abortion is indirect, then it is not. So the fact that an end is an unintended bad consequence does not reveal if that end is also the moral object or not.
 Pope John Paul II, Veritatis Splendor, n. 82.
Moreover, the fact that the death is unintended does not prove that the third font is good. Intending a bad consequence as an end would make the first font bad. What determines the morality of the third font is the proportionality of the good and bad consequences. To be moral, the third font must not do more harm than good. But the mere fact that a bad consequence is unintended does not establish that any good consequences equal or outweigh the bad. The third font can still be bad, making the overall act a sin, even if the bad consequences are unintended.
It is a common error to cite an evil as an unintended effect, and then to draw the false conclusion that this evil cannot be the moral object. Yet it is always the case, for the intrinsically evil act of euthanasia, that the death of the innocent is unintended in the first font, and is a bad consequence in the third font. The conclusion is unwarranted, therefore, that the act is moral, or that the death of the innocent cannot also be the moral object. The Magisterium condemns all acts of euthanasia as intrinsically evil and always gravely immoral. 
 Pope Saint John Paul II, Evangelium Vitae, n. 65.
The intention and circumstances do not reveal the moral object of the act. Therefore, to find the moral object, we must determine which particular act is being knowingly chosen and then consider the inherent ordering of that act towards its object.
More in my booklet: Roman Catholic Teaching on Intrinsic Evil
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