AQUINAS ON LAW
Much later in the Summa theologiae, Thomas turns to the problem of
law. His treatment of the subject shows the coherence of Thomas' thought and his
confidence in the ability of reason to guide us in making ethical decisions. The
sections is reproduced here in streamlined form, with only the responsio sections
included and with some articles omitted entirely.
Whether law is something pertaining to reason
Law is a rule and measure of actions through which one is induced to act or
restrained from acting. Lex, "law," is derived from ligare, "to bind," because it
binds one to act. The rule and measure of human activity is reason, however, for
it is the first principle of human acts. Indeed, it is the function of reason to order
to an end, and that is the first principle of all activity according to Aristotle. That
which is the first principle in any genus is the rule and measure of that genus,
e.g., unity in the genus of number or first movement in the genus of movement.
Thus it follows that law is something pertaining to reason.
Whether law is always ordered to the common good
Law pertains to that which is the principle of human acts because it is a rule
and measure. Just as reason is the principle of human acts, however, there is
something in reason which is principle of all the rest. It is to this that law
principally and mostly pertains. The first principle in activity, the sphere of
practical reason, is the final end. The final end of human life is happiness or
beatitude. Thus law necessarily concerns itself primarily with the order directing
us toward beatitude.
Furthermore, since each part is ordered to the whole as imperfect to perfect, and
since each single man is a part of the perfect community, law necessarily
concerns itself particularly with communal happiness. Thus Aristotle, in defining
legal matters, mentions both happiness and the political community, saying, "We
term 'just' those legal acts which produce and preserve happiness and its
components within the political community." For the state is a perfect
community, as he says in his Politics.
In any genus, that which is called "most of all" is the principal of everything else
in that genus, and everything else fits into the genus insofar as it is ordered to that
thing. For example, fire, the hottest thing, is cause of heat in mixed bodies, which
are said to be hot insofar as they share in fire. Thus, since law is called "most of
all" in relation to the common good, no precept concerning action has the nature
of law unless it is ordered to the common good.
Whether anyone can make laws
Law principally and properly seeks the common good. Planning for the
common good is the task of the whole people or of someone ruling in the person
of the whole people. Thus lawmaking is the task of the whole charge of the whole
people; for in all other matters direction toward an end is the function of him to
whom the end belongs.
Whether promulgation is an essential part of law
Law is imposed on others as a rule and measure. A rule and measure is
imposed by being applied to those who are ruled and measured. Thus in order for
a law to have binding power - and this is an essential part of law - it must be
applied to those who ought to be ruled by it. Such application comes about when
the law is made known to those people through promulgation. Thus such
promulgation is necessary if a law is to have binding force.
Thus from the four preceding articles we arrive at a definition of law:
Law is nothing other than a certain ordinance of reason for the common good,
promulgated by him who has care of the community.
Whether there is an eternal law
A law is nothing more than a dictate of the practical reason emanating
from a ruler who governs some perfect community. Assuming that the world is
ruled by divine providence, however, it is clear that the whole community of the
universe is governed by divine reason. Thus the very idea of the governance of
all things by God, the ruler of the universe, conforms to the definition of a law.
And since, as we read in Proverbs 8:23, the divine reason's conception of things
is eternal and not subject to time, a law of this sort can be called eternal.
Whether there is a natural law in us
Since law is a rule or measure, it can be in something in two ways: As that
which regulates and measures, or as that which is regulated and measured, for
insofar as something participates in a rule or measure it is itself regulated and
measured. Since everything subjected to divine providence is regulated and
measured by eternal law, it is clear that everything participates in the eternal law
in some way. That is, everything inclines to its own proper acts and ends because
such an inclination is impressed on it through eternal law.
The rational creature is subject to divine providence in a more excellent
way than other beings, however, for he is a participant in providence, providing
both for himself and for others. Thus he is a participant in that eternal reason
through which he has a natural inclination to his proper act and end, and this
participation of the rational creature in eternal law is called "natural law."
Thus the psalmist says, "Offer a sacrifice of justice" (Ps. 4:6) and then, as
if someone were asking him what the works of justice are, he adds, "Many say,
'Who shows us good things?'" He replies, "The light of your countenance is
impressed upon us, Lord," thus implying that the light of natural reason, by
which we discern what is good and bad (which is the function of natural law), is
nothing else than an impression of the divine light upon us.
Thus it is clear that natural law is nothing other than the rational creature's
participation in the eternal law.
Whether there is a human law
Law is a certain dictate of practical reason. The process is the same in the case of
practical and speculative reason. Each proceeds from certain premises to certain
conclusions. Accordingly it must be said that, just as in speculative reason we
draw from naturally known, in demonstrable principles the conclusions of
various sciences, and these conclusions are not imparted to us by nature but
discovered by the work of reason, so it is that human reason starts from the
precepts of natural law as from certain common and in demonstrable premises,
proceeding from them to more particular determinations of certain matters.
These particular determinations devised by human reason are called
"human laws," provided that all the other conditions included in the definition of
"law" are observed. Thus Tully says that "justice took its start from nature, then
certain things became customary because of their usefulness. Later the things
which started in nature and were approved by custom were sanctioned by fear
and reverence for the law."
Whether it was necessary that there should be a divine law
It was necessary for the direction of human life that, beyond natural and
human law, there should be a divine law. There are four reasons for this need.
First, it is through law that man is directed to the acts which are proper to
him in view of his ultimate end. If man were ordered only to an end which did
not exceed his natural faculties, it would not be necessary for him to have any
rational direction beyond natural law and that human law derived from it. Since,
however, man is ordered to the end of eternal beatitude, which exceeds natural
human faculties, it was necessary that he be directed to this end by divinely-given
law in addition to natural and human law.
Second, due to the uncertainty of human judgment, particularly regarding
contingent and particular things, there tend to be differing judgments regarding
human acts, from which proceed diverse and contrary laws. Therefore, in order
for man to be secure in the knowledge of what should be done and what avoided,
it was necessary that his acts be directed by a divinely-given law which cannot
Third, man can make laws in those areas where he is competent to judge.
His judgment does not extend to interior acts which lie hidden, however, but only
to exterior acts which are apparent. Nevertheless, perfect virtue involves
righteousness in both. Thus human law was unable to curb and direct internal acts
sufficiently, and it was necessary that divine law supervene in this task.
Fourth, as Augustine says, human law cannot punish or prohibit all things
that are evil, for in the process of removing evil it would also eliminate much
that is good and impede the advancement of the common good, thus hurting
society. Thus, in order to leave no evil unprohibited and unpunished, a divine
law, through which all sins are punished, had to intervene.
These four causes are touched upon in the Psalm, where it is said (Ps.
18:8), "The law of the Lord is unspotted" (that is, permitting no foulness of sin),
"converting souls" (because it directs not only exterior but also interior acts),
"the testimony of the Lord is sure" (due to certainty of truth and rectitude),
"giving wisdom to little ones" (insofar as it orders man to a supernatural and
Whether the eternal law is the supreme pattern of all things existing in the mind
Just as the pattern of something made by an artist pre-exists in the artist's mind,
so in the mind of any governor there pre-exists a pattern of the things to be done
by his subjects. Moreover, just as the pattern of things to be made through art is
called the art or exemplar, so the governors pattern for the activity of his subjects
takes on the nature of law provided that the other above-mentioned characteristics
of law are also present.
God, through his wisdom, is creator of all things and related to them as
artist to work of art. He is also governor of all actions and activities found in
individual creatures. Thus, just as the divine wisdom, insofar as all things were
created by it, has the character of art, exemplar or idea, so also divine wisdom as
moving all things to their proper end has the character of law. Accordingly the
eternal law is nothing other than the pattern of divine wisdom according to which
it directs all acts and motions.
Whether the eternal law is known to all
A thing can be known in two ways: First, in itself; second, in its effect, in
which some likeness of it is found, just as someone who does not see the sun in its
substance may at least know it by its rays. Thus it must be said that only God and
the blessed who see God in his essence can know the eternal law as it is in itself;
yet every creature knows it according to some of its greater or lesser radiations.
Every knowledge of truth is a certain radiation of and participation in the
eternal law, which is the unchangeable truth, as Augustine says. Everyone knows
the truth to some extent, since at least the common principles of natural law are
available to him. As for the rest, people know it in greater or lesser degree and
thus know more or less of the eternal law.
Whether all law is derived from the eternal law
Law is a certain plan directing acts to their end. Wherever movers are
ordered to one another, the power of the second mover must be derived from
that of the first, since the second mover operates only insofar as it is moved by
the first. We see the same thing in all governors. The plan of government is
derived by the secondary governors from the primary governor, just as the plan
of what is to be done in a state derives from the king through his command to
lesser administrators. It is the same in construction, where building plans descend
from the architect to the lesser craftsmen who work with their hands.
Therefore, since the eternal law is a plan of government in the supreme
governor, all plans of government in lesser governors must be derived from
eternal law. All laws besides the eternal law are plans of this sort devised by
inferior governors. Thus all laws are derived from eternal law insofar as they
participate in right reason. That is why Augustine says that "in temporal law
nothing is just and legitimate which men have not derived from eternal law."
Whether the contingent acts of nature are subject to the eternal law
Certain distinctions should be made between human law and eternal law,
which is the law of God. Human law extends only to rational creatures subject to
man. the reason for this is that law governs the actions of those who are subject to
the government of someone. Thus no one, properly speaking, imposes a law on
his own acts. Whatever is done regarding the use of irrational things subject to
man is done by man himself moving these things, since these irrational creatures
do not move themselves but are moved by others. consequently man cannot
impose law on irrational creatures, no matter how thoroughly these creatures
may be subjected to him. He can impose law on rational creatures who are subject
to him, however, insofar as by his precept or command he impresses on their
minds a rule which becomes a principle of action.
Just as man, by such precepts, impresses a kind of inward principle of
actions on whoever is subject to him, so God imprints on the whole of nature the
principles of his own proper actions, and thus he is said to command all of
nature. As the psalmist says, "He has made a decree which will not pass away"
(Ps. 148:6). For this reason all the movements and activities of nature are subject
to eternal law. Thus irrational creatures are subject to eternal law inasmuch as
they are moved by divine providence, though not by understanding of divine
commandment as in the case of rational creatures.
Whether all human affairs are subject to eternal law
A thing can be subject to eternal law in two ways: First, insofar as it
participates in the divine law by way of knowledge; second, through acting and
being acted upon, insofar as it participates in the divine law as an interior motive
principle. Irrational creatures are subject to eternal law in this second way, as
was said above.
Since a rational creature, in addition to what it shares in common with all
creatures, has some special characteristics precisely because it is rational, it is
subject to the eternal law in both ways. It has some knowledge of the eternal law,
yet at the same time there is implanted in every rational creature a natural
inclination to that which is consonant with eternal law. As Aristotle says, "We are
naturally adapted to receive the virtues."
Each manner of participating in the eternal law is imperfect and corrupted
in the wicked, for in them the natural inclination to virtue is corrupted by vicious
habits and the natural knowledge of good is overshadowed by passions and sinful
habits. Each manner is found in a more perfect condition in the good, for in them
natural understanding of the good is supplemented by knowledge through faith
and wisdom, while natural inclination toward good is supplemented by the inner
power of grace and virtue.
Thus the good are perfectly subject to eternal law in the sense that they
always act according to it. The evil are also subject to eternal law. They are
imperfectly subject to it as far as their own actions are concerned, since they
know the good imperfectly are imperfectly inclined to it. Nevertheless, this
deficiency in their action is made up by the way they are acted upon, for they
suffer the penalty decreed by the eternal law for those who do not fulfill its
Whether natural law contains many precepts or only one
The precepts of natural law are related to practical reason as the first
principles of demonstration are to speculative reason. Both are self-evident
A thing is said to be self-evident in two ways, in itself and for us. A
proposition is said to be self-evident because the predicate is contained in the
definition of the subject; yet it will not be self-evident to someone who does not
know the definition of the subject. Thus the proposition "man is rational" is self-
evident because "rational" is part of the definition of man," but it is not self-
evident to anyone who does not know what a man is.
Thus, as Boethius says, "Certain axioms or propositions are self-evident to
all," and these are propositions the terms of which are understood by all, such as
"the whole is greater than the part" or "things equal to a third thing are equal to
one another." On the other hand, some propositions are self-evident only to the
wise, who understand what the words mean. Thus, to anyone who knows that an
angel is not a body, it is self-evident that an angel is not circumscriptively present
in a place; yet that is not at all self-evident to the uneducated, who do not
There is, however, a certain order to those things which fall within the
apprehension of man. The first thing which falls within his apprehension is being,
the notion of which is included in everything he apprehends. Thus the first in
demonstrable principle, that the same thing cannot be simultaneously affirmed
and denied, is based on the very notion of being and non-being, and all other
principles are founded on this one, as Aristotle says.
Just as being is the first thing which falls within the apprehension as such,
so good is the first thing to fall within the apprehension of practical reason,
which is ordered to activity. For every agent pursues an end which is perceived
as good. Thus the first principle for practical reason is a definition of the good,
namely that "the good is that which all men seek after." Thus the first precept of
the law is that "good is to be pursued and performed, evil avoided." On this
principle is founded all others in natural law. Thus whatever practical reason
recognizes to be good for man pertains to the precepts of natural law.
Since from this perspective the good is defined as an end to be pursued,
while evil is defined as what is contrary to that end, reason naturally sees as good
and therefore to be pursued all those things to which man has a natural
inclination, while it sees the contraries of these things as evil and therefore to be
Thus the order of precepts in natural law follows the order of natural
inclinations. First of all, within man there is an inclination to good according to
the nature he shares in common with all substances. Every substance seeks to
preserve its own being according to its nature. Because of this inclination, all the
things through which man's life is preserved belong to natural law.
Second, within man there is an inclination to certain more special things
according to the nature he has in common with other animals. Because of this
inclination, those things which nature has taught to all animals are said to be part
of natural law. This would include sexual intercourse, education of offspring, and
Third, within man there is an inclination to good according to his own
particular nature as rational. For example, he has a natural inclination to know
the truth about God and to live in society. Inclinations of this sort also pertain to
natural law, and thus it is part of natural law that man should shun ignorance,
avoid offending those with whom he has to live, etc.
Whether natural law is the same for all
Those things to which man is naturally inclined pertain to natural law.
Among such inclinations is one particular to man: The inclination to act
according to reason. Reason characteristically proceeds from the general to the
particular, as Aristotle says. Speculative reason differs from practical reason in
this respect, however. Since speculative reason deals primarily with necessary
things which cannot be otherwise than they are, both its general premises and its
particular conclusions are unerringly true. Practical reason, however, deals with
contingent matters involving human activity. Thus, even if the general premises
are necessary, the more we descend to particulars the more frequently we
Thus in speculative matters the same truth is found in premises and in
conclusions, although the truth of the conclusions is not recognized by all, but
only that of the premises, which are called "common notions." In matters of
actions, however, truth or practical rectitude is not always the same in particular
instances, but only in general premises. Moreover, even when there is the same
rectitude in particular cases, it is not equally recognized by all.
Thus it is obvious that in the case of general premises there is always the
same truth or rectitude, whether one is dealing with speculative or practical
reason. In the case of speculative reason, particular conclusions are true in all
cases, though their truth may not be equally recognized by all. A triangle always
has three angles the sum of which is equal to two right angles, even though
everyone does not know this. In the case of practical reason, however, particular
conclusions are not true in every case, nor, even when they are, is their truth
It is invariably correct that we should act according to reason. It follows
from this premise that goods held in trust should be returned to their owners, and
such is, in fact, usually the case; yet some situations might occur in which it was
harmful and therefore irrational to return goods held in trust. For example, the
person might request his goods because he wanted to use them to attack his
country. The more one descends to particular cases, the more the general rule
admits exceptions, and one finds oneself stipulating that goods held in trust must
be restored with such and such a guarantee or in such and such a way; for the
more conditions are added, the more ways one finds in which the general rule can
fail and the less helpful the general rule by itself becomes in deciding whether or
not the goods should be returned.
Thus it must be said that in its general premises natural law is always the
same in itself and is commonly seen to be such. In the particular determinations
drawn from those general premises, natural law is the same in most cases and is
so perceived by most people; yet in a few cases it can fail in itself because of
particular impediments (just as the natural processes of generation and decay
occasionally fail because of impediments), and it can also fail to be recognized as
true because the reasons of some are distorted by passion, evil habits, or evil
natural disposition. Thus Julius Caesar remarks that the Germans once did not
regard theft as evil.
Whether natural law can be changed
There are two ways in which one can speak of natural being changed. The
first is by something being added to it. Nothing would prevent it from being
changed in this way, for many things useful to human life have been added to
natural law, both by divine law and by human law.
The second way is by subtraction, when something which used to be part
of natural law ceases to be such. The first principles of natural law are absolutely
immutable. Its secondary precepts, which we have described as certain particular
conclusions close to first principles, cannot be changed in such a way that its
application in the majority of cases is altered, but in some few cases it can be
changed in some particular, due to some special causes impeding the normal
observance of such precepts.
Whether it was useful for human laws to be made by man
There is a certain aptitude for virtue in man, but the perfection of that
virtue must be achieved through training. In the same way we see that industry
aids man in achieving necessities like food and clothing; for he has the beginnings
of these things from nature - that is, nature gives him reason and a pair of hands -
but not the complete product, as is the case with other animals to whom natures
gives food and clothing. It is hard for a single man to gain such training by
himself, for the perfection of virtue consists in withdrawing from undue
pleasures, to which men are particularly prone. This is particularly true of the
young, who are also more easily trained. Thus the training through which men
come to virtue needs to be received from someone else.
In the case of those young people who are inclined to acts of virtue by
natural disposition, by habit, or by divine gift, paternal discipline in the form of
friendly reminders will be sufficient. Nevertheless, since some are not easily
moved by words because they are depraved and inclined to vice, it is necessary
for such to be restrained from evil by force and fear, so that they will at least
stop their evil-doing and leave others in peace, or perhaps eventually, by force of
habit, be brought to do willingly what they formerly did through fear, thus
becoming virtuous. This kind of training, which compels through fear of
punishment, is the training of laws.
Thus it was necessary for peace and virtue that there be laws. As Aristotle
says, "If man is perfected by virtue, he is the best animal. If he is separated from
law and justice, he is the worst." Such is the case because man can use the
weapons of reason, which other animals lack, to satisfy his lust and rage.
Whether every human law is derived from natural law
As Augustine says, "There never seems to have been a law that was not
just." Thus it has the force of law insofar as it is just. In human affairs, something
is said to be just insofar as it is right according to the rule of reason. The first
rule of reason is, however, natural law. Thus every human law has the nature of
a law insofar as it is derived from natural law. If it conflicts with natural law in
any way, then it is not law but a corruption of law.
But it should be noted that something can be derived from the natural law in two
ways: First, as conclusions from premises; second, as determinations of certain
generalities. The first way is similar to that in which conclusions are
demonstratively derived from premises in the sciences. The second is similar to
the way general ideas are given special shape in the arts, as when a builder
decides that he will actualize the general form of a house by constructing this or
that particular model.
Thus some laws are drawn as conclusions from the general principles of
natural law. For example, "you must not commit murder" can be derived as a
conclusion from "you must do harm to no one." Other laws are drawn from
natural law by way of determination. For example, natural law requires that he
who sins should be punished, but that he be punished by this or that punishment is
a determination of natural law. Both are found in human law, but the first sort
derive their strength, not only from the fact that they are legally enacted, but also
from natural law itself. The second sort derive their strength only from human
Whatever is directed to an end should be proportioned to that end. The end
of law is the common good, because, as Isidore says, "Law should be written, not
for private gain, but for the general welfare of the citizens." Thus laws should be
proportioned to the common good.
This good is comprised of many things, and thus law should take many
different persons, occupations and situations into account. A political community
is composed of many people and its good is secured through many actions. Nor is
it created to last a short time, but for a very long time and through generations of
citizens, as Augustine says.
Whether it is the business of human law to restrain all vice
Law is established as a certain rule or measure of human actions. A
measure ought to be of the same type as the thing measured, as Aristotle
observes, for different things have different standards, Thus laws should be
imposed on men: according to their condition, because, as Isidore says, "Law
should be possible according to the customs of the land."
The power or possibility of action springs from an internal habit or
disposition. Actions that are possible to a virtuous man are not possible to him
who lacks the habit of virtue, any more than a boy can do all that a grown man
can do. Thus the same law is not imposed on adults and children alike, and many
things permitted to children are punished or at least blamed when performed by
adults. Similarly, many things are permitted to men imperfect in virtue which
would not be tolerated in more virtuous men.
Human law is imposed on the multitude, a part of which is composed of
men imperfect in virtue. Thus all the vices from which the virtuous abstain are
not punished by human law, but only the more grievous ones which most people
can avoid, and especially those which can hurt others, without the prohibition of
which human society could not be preserved. Thus homicide, theft and the like
are prohibited by human law.
Whether human law prescribes all virtuous acts
Virtues are differentiated according to their objects. These objects all
involve either the private good of an individual or the common good of the
multitude. Thus an act of courage may be performed to preserve one's city or to
preserve the rights of a friend. It is the same with other virtues.
Law, however, is ordered to the common good. Thus there is no virtue the
acts of which cannot be prescribed by law. Nevertheless, law does not prescribe
every act of every virtue, but only those which are ordained to the common
good, either immediately as when things are done directly for the common good,
or mediately as when a lawgiver prescribes certain things pertaining to good
discipline through which the citizens will be trained to preserve peace and justice.
Whether human law binds a man's conscience
Human laws are either just or unjust. If they are just, they have the power
to bind our conscience because of the eternal law from which they are derived.
As Proverbs says, "Through me kings reign and lawmakers decree just laws"
Laws are said to be just either because of their end, when they are
ordained to the common good; or because of their author, when the law does not
exceed the power of the lawmaker; or because of their form, when burdens are
distributed equitably among subjects for the common good. For since a man is
part of the multitude, whatever he is or has belongs to the multitude as a part
belongs to the whole. Thus nature inflicts harm on a part in order to save the
whole. Accordingly laws which inflict burdens equitably are just, bind the
conscience, and are legal laws.
Laws are unjust in two ways: First, they may be such because they oppose
human good by denying the three criteria just mentioned. This can occur because
of their end, when a ruler imposes burdens with an eye, not to the common good,
but to his own enrichment or glory; because of their author, when someone
imposes laws beyond the scope of his authority; or because of their form, when
burdens are inequitably distributed, even if they are ordered to the common
good. Such decrees are not so much laws as acts of violence, because, as
Augustine says, "An unjust law does not seem to be a law at all." Such laws do not
bind the conscience, except perhaps to avoid scandal or disturbance, on account of
which one should yield his right. As Christ says, "If someone forces you to go a
mile, go another two with him; and if he takes your tunic, give him your
pallium" (Mtt. 5:40f.).
Second, laws may be unjust because they are opposed to the divine good, as
when the laws of tyrants lead men to idolatry or to something else contrary to
divine law. Such laws must never be observed, because "one must obey God
rather than men" (Acts 5:29).
Whether someone subject to the law can act outside the letter of the law
All law is ordered to the common well-being of men and gains the force of
law from precisely that fact. To the degree that it fails in accomplishing this end,
it loses its binding force. Thus the Jurist says, "No reason of law or advantage of
equity allows us to interpret harshly and render burdensome those healthy
measures which were originally enacted for man s welfare."
It often happens that a law aimed at the general welfare is useful in most cases
and yet on occasion is very harmful. Because a legislator cannot foresee all
possible individual cases, he promulgates a law which fits the majority of cases,
having the common good in mind. If a case emerges in which the law is harmful
to the common good, it should not be observed. For example, if a law says that
the gates of a certain besieged city should remain closed, such a law is beneficial
to the city in most cases; yet if the enemy is pursuing some of the very citizens by
whom the city is defended, refusal to open the gates and let them in would be
harmful to the city. In such cases, the gates should be opened despite the letter of
the law, in order to attain the common good intended by the legislator.
Note, though, that if obedience to the letter of the law involves no
immediate danger calling for instant remedy, not everyone is competent to decide
what is good or bad for the city, but only the leaders, who have authority to
dispense with the law in such cases. If it is indeed a matter of immediate danger
allowing no time to consult a superior, such necessity carries its own
dispensation, for necessity knows no law.
Whether human law should be changed in any way
Human law is a dictate of reason by which human actions are directed.
Thus change in law has a twofold source: One on the part of reason, the other on
the part of the men whose actions are regulated by law.
On the part of reason, it can be changed because it seems natural for
human reason to advance gradually from the imperfect to the perfect. Thus we
see in the speculative sciences that the early philosophers produced imperfect
teachings which were later improved by their successors. So also in the practical
realm, those who first tried to discover what was beneficial for human
community, being unable to think everything through by themselves, created
imperfect situations which were lacking in many ways. These institutions were
then altered by subsequent lawmakers, producing institutions which departed
from the common good in fewer instances.
On the part of the men whose activities are regulated by law, a law is
rightly changed when there is a change in the conditions of men, for different
things are expedient in accordance with different conditions. Augustine offers the
following example: "If the people are moderate, responsible, and careful
guardians of the common good, it is proper to enact a law allowing them to
choose magistrates through whom the commonwealth can be administered. If,
however, in time the people become corrupted and sell their votes, entrusting the
government to scoundrels and criminals, they forfeit their power to elect public
officials and the right devolves upon a few good men.
Whether human law should always be changed when something better is possible
It is right to change human law if such a change is conducive to the
common good. Nevertheless, the very act of changing a law damages the common
good to some extent, because custom encourages people to observe the law. Even
minor changes seem to be major when they involve a breach of custom. Thus
when a law is changed its binding force is diminished insofar as custom is
abolished. For this reason, human law should never be changed unless the
advantage to the common good resulting from its alteration outweighs the damage
done by the change itself.
Such may be the case if some great and evident benefit is derived from the
new law, or if some extreme emergency is occasioned by the fact that the existing
law is clearly unjust or its observance extremely harmful new laws the benefit to
be derived should be evident before one dispenses with a law that was long
Translation by David Burr [email@example.com]. See his home page. He indicated that the translations are available for educational use. He intends to expand the number of translations, so keep a note of his home page.
Paul Halsall Jan 1996