Article I: On the Intrinsic Difference Between Good and Evil

St. Thomas, I-II, q. 18, a. 1 and 8; Contra Gentiles III, 129.

121. State of the question. - First it occurs to ask concerning the reason for the difference between good and evil, whether, namely, there are some human acts which are objectively good or evil intrinsically, or from the nature of the thing, or on the contrary whether they are such only from an extrinsic determination and positive will. Concerning this there are several errors, which are comprehended under the common name of moral positivism.

They are reduced to two classes:

1. For some say that the positive determination of good and evil was made by men, whether a) by civil laws (Hobbes) or by social contract (Rousseau), or b) by education (Montaigne), or c) by public opinion and the custom of peoples (St. Lambert), or d) by the invention of the wise and powerful (Mandeville), or e) by the evolution of the moral sense or of the collective conscience or of culture (Evolutionists, v. Hartmann, Levy-Bruhl, Durkheim).

2. Others derive the distinction from the free will of God: thus the Nominalists, such as Occam and Gerson, Descartes, Pufendorf, likewise commentators of Grotius, such as Osiander, Gronovius, Cocceius.

1. Among the ancients, Archelaus, the Sophists Protagoras and Gorgias, Theodorus Cyrenaicus, Pyrrho the skeptic, and Carneades are said to have taught thus; in more recent times, A. Comte, Kirchmann, R. v. Ihering, perhaps also Fr. Paulsen; likewise Fr. Jodl, Ed. Westermarck, Bebel, Kautsky, and many others, among whom are M. Stirner and Fr. Nietzsche, who asserted that all morality is an arrogant falsification introduced by fraud in favor of the miserable: for the "superior" man is outside the limits of good and evil.

2. Scotus also is sometimes cited, but he teaches this only concerning the precepts of the second table, in III Sent. d. 27, q. un., sch. 5-8.

Against these Catholic doctrine holds that certain actions are good or evil from their own nature, independently of every positive will.

122. Thesis. Certain actions are given which are intrinsically good or evil, independently of any will whatever, even the divine will.

We indeed admit that there are many actions which are morally good because they have been commanded by some divine or human law, and similarly many which are evil because they have been prohibited; but some are commanded or prohibited as honorable or dishonorable in themselves.

It is proved: 1) by an argument from conscience and historical induction. It is established psychologically and historically that there are certain actions which, from the common conscience and the perpetual and invincible persuasion of men, have always been held as naturally honorable or dishonorable in themselves: thus, for example, to love parents, to do good to one's neighbor, to speak the truth, to keep agreements, etc.; on the other hand, to pursue parents with hatred, to kill the innocent without a legitimate reason, to betray friends unjustly, to break promises, to utter a lie harmful to one's neighbor, and other things of the same kind, are judged as something base and dishonorable. This persuasion indeed flourishes among all peoples, even barbarous ones; nor is it diminished or lost by anyone unless the moral sense is diminished or destroyed. But a persuasion so constant and universal, deeply inhering in minds so diverse and disagreeing about almost all other things, does not arise from civil law or custom, which is diverse among various nations, and besides, laws and customs are called good and evil, for which reason they are not the primary criterion; nor from education, social contract, or public opinion, which likewise are not the same among diverse peoples; but it is derived from nature itself.

Nor can it be said that the morality of these acts depends upon a free institution of God: for this institution is not known by many peoples who do not have revelation, whence it does not explain the universality of the fact. Moreover, certain actions appear of themselves and essentially so honorable or dishonorable that not even the divine will can change their morality (e.g., God cannot make blasphemy be a praiseworthy act, nor piety be a sin): namely, the essences of things do not depend upon the free will of God, and consequently neither do the essential relations among them. Whence St. Thomas, Q. D. De Ver. 23, a. 6: "The will does not have the character of the first rule...; for it is directed by reason and intellect, not only in us, but in God...; to say that justice depends upon the simple will is to say that the divine will does not proceed according to the order of wisdom, which is blasphemous."

2. From philosophical reason: the good of a being is that which agrees with its nature; evil, that which disagrees. And there are several actions which per se and naturally agree or disagree with rational human nature. Therefore there are several actions which, from their very nature, per se and naturally, are good or evil.

The minor is proved from St. Thomas, III Contra Gentiles 129: "Of whatever things there is a determinate nature, there must be determinate operations which agree with that nature (or on the contrary disagree): for the proper operation of each thing follows its nature. But it is established that the nature of men is determinate. Therefore there must be some operations fitting to man according to themselves" (or on the contrary unfitting).

The conclusion is proved inductively from the three principal matters about which human action is occupied, that is, concerning a) social relations with others, insofar as man is a social being; b) the use of exterior things and the governance of the body and of the lower powers, insofar as he is a rational being; c) relations with God, the ultimate end, insofar as man is a created being. And in these three matters actions are by their own nature fitting or unfitting:

a) concerning social relations with other men: "For anything to which something is natural, that without which it cannot be had must be natural: for nature does not fail in necessary things. But it is natural to man that he be a social animal; this is shown from the fact that one man alone does not suffice for all things which are necessary for human life. Therefore those things without which human society cannot be preserved are naturally fitting to man: of this sort are preserving to each one what is his, and abstaining from injuries. Therefore there are some things in human acts naturally right."

b) concerning the use of exterior things and the governance of the body and of the lower powers: "Man naturally has this, that he use lower things for the necessity of his life. But there is some determinate measure naturally according to which the use of the aforesaid things is fitting to human life, and if this measure is passed over, it becomes harmful to man, as is clear in the disordered taking of foods. Therefore there are some acts naturally unfitting to man.

"Likewise, according to the natural order, the body of man is for the sake of the soul and the lower powers of the soul for the sake of reason; just as also in other things matter is for the sake of form and instruments for the sake of the principal agent. But from that which is ordered to another, help ought to come to that other, not some impediment. Therefore it is naturally right that the body and the lower powers of the soul be so cared for by man that from this the act of reason and the good of reason itself be in no way impeded, but rather helped. But if it should happen otherwise, it will naturally be sin. Therefore drunkennesses and feastings and the disordered use of venereal things, by which the act of reason is impeded, and to be subject to passions, which do not allow the free judgment of reason to exist, are naturally evil."

c) concerning relations with God: "To each one there are naturally fitting those things by which it tends to its natural end; but those things which have themselves contrariwise are naturally unfitting to it... Man is naturally ordered to God as to an end. Therefore those things by which man is led into the knowledge and love of God are naturally right; but whatever things have themselves contrariwise are naturally evil to man."

"It is clear therefore, as St. Thomas concludes, that good and evil in human acts are not only according to the positing of law, but also according to the natural order."

3. From the consequences of the opposed opinion: if there is no essential and objective difference between good and evil, a broad way is opened to moral skepticism. For a) what today is held as evil, tomorrow, with laws changed, or tradition or education, can be held as licit; and therefore the true notion of moral obligation perishes: for this is conceived as something permanent and universal, prescribing certain actions not hypothetically but categorically, while civil laws or traditions of peoples are something unstable and particular, and can create only a hypothetical obligation. Therefore, once this difference has been removed, by that very fact the moral order collapses; b) certain customs have existed which were very wicked, the attack upon which, led by heroic and holy men, is generally praised as progress. And yet according to positivism all morals are good; nor is an ideal and permanent rule given for measuring progress; c) as a foundation the adversaries must suppose the principle: to obey God commanding (or men commanding) is good, and to resist is evil. Therefore some good or evil must be admitted before the positive precept of God (or of men). And if none is admitted, the foundation of the whole moral order collapses.

123. They object.

The positivists and evolutionists object with certain examples concerning polygamy, human sacrifices, and the killing of parents from piety, namely, to avoid the inconveniences of old age or captivity, which at times are reputed honorable and just; whence they conclude that the public conscience is not injured by a delict because the act is evil, but on the contrary the act is evil because it injures the public conscience.

Reply: Error exists not as to all things intrinsically honorable and dishonorable, but as to some things: namely, nature can fail not in all things but in some, and thus some have a depraved reason from passion, or from bad custom, or from a bad disposition of nature, and they could err as to some things, as in the case of polygamy, or human sacrifice, or robbery, which among some was not reputed unjust, or the killing of parents perpetrated to take away misery. But rather they erred about the mode of cultivating piety than about the obligation itself of helping parents; just as about the mode of worshiping God, preserving justice, or ordering marriage, not about the principles themselves, that it is good to love God, to live justly, and to protect the education of the human race through marriage. Whence already St. Thomas says, in Ethics, book 3: "Certain things (not all), which by some are reputed just and honorable, by some are reputed unjust and dishonorable according to the difference of times and places and persons. For something is reputed vicious at one time or in one region which at another time or in another region is not reputed vicious. And from this difference it happens that some opine that nothing is naturally just or honorable, but only according to the positing of law."