## 1. Key Features of Natural Law Theories



Even though we have already confined 'natural law theory'
to its use as a term that marks off a certain class of ethical
theories, we still have a confusing variety of meanings to contend
with. Some writers use the term with such a broad meaning that any
moral theory that is a version of moral realism -- that is, any
moral theory that holds that some positive moral claims are literally
true (for this conception of moral realism, see Sayre-McCord
1988)-- counts as a natural law view. Some use it so narrowly
that no moral theory that is not grounded in a very specific form of
Aristotelian teleology could count as a natural law view. It might be
thought that there is nothing that can be done to begin a discussion
of natural law theory in ethics other than to stipulate a meaning for
'natural law theory' and to proceed from there. But there
is a better way of proceeding, one that takes as its starting point
the central role that the moral theorizing of Thomas Aquinas plays in
the natural law tradition. If any moral theory is a theory of natural
law, it is Aquinas's. (Every introductory ethics anthology that
includes material on natural law theory includes material by or about
Aquinas; every encyclopedia article on natural law thought refers to
Aquinas.)  It would seem sensible, then, to take Aquinas's
natural law theory as the central case of a natural law position: of
theories that exhibit all of the key features of Aquinas's
natural law view we can say that they are clearly natural law
theories; of theories that exhibit few of them we can say that they
are clearly not natural law theories; and of theories that exhibit
many but not all of them we can say that they are in the neighborhood
of the natural law view but nonetheless must be viewed as at most
deviant cases of that position. There remain, no doubt, questions
about how we determine what are to count as the *key* features
of Aquinas's position. But we may take as the key features those
theses about natural law that structure his overall moral view and
which provide the basis for other theses about the natural law that he
affirms. 



For Aquinas, there are two key features of the natural law, features
the acknowledgment of which structures his discussion of the natural
law at Question 94 of the Prima Secundae of the *Summa
Theologiae*. The first is that, when we focus on God's role
as the giver of the natural law, the natural law is just one aspect of
divine providence; and so the theory of natural law is from that
perspective just one part among others of the theory of divine
providence. The second is that, when we focus on the human's
role as recipient of the natural law, the natural law constitutes the
principles of practical rationality, those principles by which human
action is to be judged as reasonable or unreasonable; and so the
theory of natural law is from that perspective the preeminent part of
the theory of practical rationality.


### 1.1 Natural law and divine providence



While our main focus will be on the status of the natural law as
constituting the principles of practical rationality, we should
consider for a moment at least the importance within Aquinas's
view of the claim that the natural law is an aspect of divine
providence. The fundamental thesis affirmed here by Aquinas is that
the natural law is a participation in the eternal law (ST IaIIae 91,
2). The eternal law, for Aquinas, is that rational plan by which all
creation is ordered (ST IaIIae 91, 1); the natural law is the way that
the human being "participates" in the eternal law 
(ST IaIIae 91, 2). While nonrational beings have a share in the
eternal law only by being determined by it -- their action
nonfreely results from their determinate natures, natures the
existence of which results from God's will in accordance with
God's eternal plan -- rational beings like us are able to
grasp our share in the eternal law and freely act on it  (ST
IaIIae 91, 2). It is this feature of the natural law that justifies,
on Aquinas's view, our calling the natural law
'law.'  For law, as Aquinas defines it (ST IaIIae 90,
4), is a rule of action put into place by one who has care of the
community; and as God has care of the entire universe, God's
choosing to bring into existence beings who can act freely and in
accordance with principles of reason is enough to justify our thinking
of those principles of reason as law.


### 1.2 Natural law and practical rationality



When we focus on the recipient of the natural law, that is, us human
beings, the thesis of Aquinas's natural law theory that comes to
the fore is that the natural law constitutes the basic principles of
practical rationality for human beings, and has this status by nature
(ST IaIIae 94, 2). The notion that the natural law  constitutes
the basic principles of practical rationality implies, for Aquinas,
both that the precepts of the natural law are universally binding by
nature (ST IaIIae 94, 4) and that the precepts of the natural law are
universally knowable by nature (ST IaIIae 94, 4; 94, 6). 



The precepts of the natural law are binding by nature: no beings could
share our human nature yet fail to be bound by the precepts of the
natural law. This is so because these precepts direct us toward the
good as such and various particular goods (ST IaIIae 94, 2). The good
and goods provide reasons for us rational beings to act, to pursue the
good and these particular goods. As good is what is perfective of us
given the natures that we have (ST Ia 5, 1), the good and these
various goods have their status as such naturally. It is sufficient
for certain things to be good that we have the natures that we have;
it is in virtue of our common human nature that the good for us is
what it is.



The precepts of the natural law are also knowable by nature.  All
human beings possess a basic knowledge of the principles of the
natural law (ST IaIIae 94, 4). This knowledge is exhibited in our
intrinsic directedness toward the various goods that the natural law
enjoins us to pursue, and we can make this implicit awareness explicit
and propositional through reflection on practice. Aquinas takes it
that there is a core of practical knowledge that all human beings
have, even if the implications of that knowledge can be hard to work
out or the efficacy of that knowledge can be thwarted by strong
emotion or evil dispositions (ST IaIIae 94, 6).



If Aquinas's view is paradigmatic of the natural law position,
and these two theses -- that from the God's-eye point of
view, it is law through its place in the scheme of divine providence,
and from the human's-eye point of view, it constitutes a set of
naturally binding and knowable precepts of practical reason --
are the basic features of the natural law as Aquinas understands it,
then it follows that paradigmatic natural law theory is incompatible
with several views in metaphysics and moral philosophy. On the side of
metaphysics, it is clear that the natural law view is incompatible
with atheism: one cannot have a theory of divine providence without a
divine being. It is also clear that the paradigmatic natural law view
rules out a deism on which there is a divine being but that divine
being has no interest in human matters. Nor can one be an agnostic
while affirming the paradigmatic natural law view: for agnosticism is
the refusal to commit either to God's existence or nonexistence,
whereas the paradigmatic natural law view involves a commitment to
God's existence. On the side of moral philosophy, it is clear
that the natural law view is incompatible with a nihilism about value,
that is, the rejection of the existence of values. It is also
incompatible with relativist and conventionalist views, on which the
status of value is entirely relative to one's community or
determined entirely by convention. It is also incompatible with a
wholesale skepticism about value, for the natural law view commits one
to holding that certain claims about the good are in fact knowable,
indeed, knowable by all.


### 1.3 The substance of the natural law view



The center of Aquinas's natural law view as described thus far
concerns what we might call the metaphysics of morals: its role in
divine providence and the universally authoritative character of its
norms. What, though, of the normative *content* of
Aquinas's natural law position?  Is there anything
distinctive about the normative natural law position?  Here it is
difficult to say much that is uncontroversial, but we can say a
sufficient amount about Aquinas's natural law theory to make
clear that it is an interesting alternative to utilitarian (and more
generally consequentialist) ethics, Kantian views, and standard
Aristotelian positions. (For a magisterial treatment of
Aquinas's natural law ethic, see Rhonheimer 2000.)



Aquinas says that the fundamental principle of the natural law is that
good is to be done and evil avoided (ST IaIIae 94, 2). This is, one
might say, a principle of intelligibility of action (cf. Grisez 1965):
only action that can be understood as conforming with this principle,
as carried out under the idea that good is to be sought and bad
avoided, can be understood as an intelligible action. But no one can
in acting simply pursue good -- one has to pursue some particular
good. And Aquinas holds that we know immediately, by inclination, that
there are a variety of things that count as good and thus to be
pursued -- life, procreation, knowledge, society, and reasonable
conduct (ST IaIIae 94, 2; 94, 3) are all mentioned by Aquinas (though
it is not clear whether the mentioned items are supposed to constitute
an exhaustive list).



So on Aquinas's view it is the good that is fundamental: whether
an action, or type of action, is *right* is logically posterior
to whether that action brings about or realizes or is some
*good*. The good is, on Aquinas's view, prior to the
right. But on Aquinas's view we are, somehow, able to reason
from these principles about goods to guidelines about how these goods
are to be pursued. Aquinas's thoughts are along the following
lines: first, there are certain ways of acting in response to the
basic human goods that are intrinsically flawed; and second, for an
act to be right, or reasonable, is for it to be an act that is in no
way intrinsically flawed (ST IaIIae 18, 1).



The important task, then, is to identify the ways in which an act can
be intrinsically flawed. Aquinas does not obviously identify some
master principle that one can use to determine whether an act is
intrinsically flawed (though for an attempt to identify such a master
principle in Aquinas's work see Finnis 1998, p. 126), though he
does indicate where to look -- we are to look at the features
that individuate acts, such as their objects (ST IaIIae 18, 2), their
ends (ST IaIIae 18, 3), their circumstances (ST IaIIae 18, 4), and so
forth. An act might be flawed through a mismatch of object and end
-- that is, between the immediate aim of the action and its more
distant point. If one were, for example, to regulate one's
pursuit of a greater good in light of a lesser good -- if, for
example, one were to seek friendship with God for the sake of mere
bodily survival rather than vice versa -- that would count as an
unreasonable act. An act might be flawed through the circumstances:
while one is bound to profess one's belief in God, there are
certain circumstances in which it is inappropriate to do so (ST
IIaIIae 3, 2). An act might be flawed merely through its intention: to
direct oneself against a good -- as in murder (ST IIaIIae 64, 6),
and lying (ST IIaIIae 110, 3), and blasphemy (ST IIaIIae 13, 2)
-- is always to act in an unfitting way. Aquinas has no illusions
that we will be able to state principles of conduct that exhaustively
determine right conduct, as if for every situation in which there is a
correct choice to be made there will be a rule that covers the
situation. He allows for the Aristotelian insight that the particulars
of the situation always outstrip one's rules, so that one will
always need the moral and intellectual virtues in order to act well
(Commentary on NE, II, 2, 259). But he denies that this means that
there are no principles of right conduct that hold everywhere and
always, and some even absolutely. On Aquinas's view, killing of
the innocent is always wrong, as is lying, adultery, sodomy, and
blasphemy; and that they are always wrong is a matter of natural law.
(These are only examples, not an exhaustive list of absolutely
forbidden actions.)



Part of the interest of Aquinas's substantive natural law ethic
lies in its not falling into the neat contemporary categories for
moral theories. His natural law view understands principles of right
to be grounded in principles of good; on this Aquinas sides with
utilitarians, and consequentialists generally, against Kantians. 
But Aquinas would deny that the principles of the right enjoin us to
maximize the good -- while he allows that considerations of the
greater good have a role in practical reasoning, action can be
irremediably flawed merely through (e.g.) badness of intention, flawed
such that no good consequences that flow from the action would be
sufficient to justify it -- and in this Aquinas sides with the
Kantians against the utilitarians and consequentialists of other
stripes. And while Aquinas is in some ways Aristotelian, and
recognizes that virtue will always be required in order to hit the
mark in a situation of choice, he rejects the view commonly ascribed
to Aristotle (for doubts that it is Aristotle's view; see Irwin
2000) that there are no universally true general principles of right.
The natural law view rejects wholesale particularism.


### 1.4 Paradigmatic and nonparadigmatic natural law theories



To summarize: the paradigmatic natural law view holds that (1) the
natural law is given by God; (2) it is naturally authoritative over
all human beings; and (3) it is naturally knowable by all human
beings. Further, it holds that (4) the good is prior to the right,
that (5) right action is action that responds nondefectively to the
good, that (6) there are a variety of ways in which action can be
defective with respect to the good, and that (7) some of these ways
can be captured and formulated as general rules.



Aquinas was not the only historically important paradigmatic natural
law theorist. Thomas Hobbes, for example, was also a paradigmatic
natural law theorist. He held that the laws of nature are divine law
(*Leviathan*, xv, P41), that all humans are bound by them
(*Leviathan*, xv, PP36), and that it is easy to know
at least the basics of the natural law (*Leviathan*, xv,
P35). He held that the fundamental good is self-preservation
(*Leviathan*, xiii, P14), and that the laws of nature
direct the way to this good (Leviathan, xiv, P3). He offered a
catalog of laws of nature that constitute the "true moral
philosophy" (*Leviathan*, xv, P40). There are also a
number of contemporary writers that affirm the paradigmatic view.
These writers, not surprisingly, trace their views to Aquinas as the
major influence, though they do not claim to reproduce his views in
detail. (See, for example, Grisez 1983, Finnis 1980,  MacIntyre
1999, and Murphy 2001.)



It is also easy to identify a number of writers, both historical and
contemporary, whose views are easily called natural law views, through
sharing all but one or two of the features of Aquinas's
paradigmatic position. Recently there have been nontheistic writers in
the natural law tradition, who deny (1): see, for example, the work of
Michael Moore (1982, 1996) and Philippa Foot (2001). There were a
number of post-Thomistic writers in the medieval and modern periods
who in some way denied (2), the natural authority of the natural law,
holding that while the *content* of the natural law is fixed
either wholly or in part by human nature, its *preceptive
power* could only come from an additional divine command: the
views of John Duns Scotus, Francisco Suarez, and John Locke fit this
mold.    Arguably the Stoics were natural law thinkers,
but they seem to deny (4), holding the right to be prior to the good
(see Striker 1986). Some contemporary theological ethicists called
'proportionalists' (e.g. Hallett 1995) have taken up the
natural law view with a consequentialist twist, denying (6). (For a
discussion of the relationship between proportionalism and natural law
theory see Kaczor 2002.) And while some see Aristotle as being the
source of the natural law tradition, some have argued that his central
appeal to the insight of the person of practical wisdom as setting the
final standard for right action precludes the possibility of the sort
of general rules that would (at least in a theistic context) make
Aristotle's ethics a natural law position. There is of course no
clear answer to the question of when a view ceases to be a natural law
theory, though a nonparadigmatic one, and becomes no natural law
theory at all.


## 2. Theoretical Options for Natural Law Theorists



Even within the constraints set by the theses that constitute the
paradigmatic natural law position, there are a number of variations
possible in the view. Here we will consider several issues that must
be addressed by every particular natural law view, and some
difficulties that arise for possible responses to these issues. 


### 2.1 Natural goodness



It is essential to the natural law position that there be some things
that are universally and naturally good. But how is universal, natural
goodness possible?  Given the variability of human tastes and
desires, how could there be such universal goods?



Natural law theorists have at least three answers available to them.
The first answer is Hobbesian, and proceeds on the basis of a
subjectivist theory of the good. On subjectivist theories of the good,
what makes it true that something is good is that it is desired, or
liked, or in some way is the object of one's pro-attitudes, or
would be the object of one's pro-attitudes in some suitable
conditions. One might think that to affirm a subjectivist theory of
the good is to reject natural law theory, given the immense variation
in human desire. But this is not so. For one might hold that human
beings' common nature, their similarity in physiological
constitution, makes them such as to have some desires in common, and
these desires may be so central to human aims and purposes that we can
build important and correct precepts of rationality around them. This
is in fact what Hobbes claims. For while on the Hobbesian view what is
good is what is desired, Hobbes thinks that humans are similarly
constructed so that for each human (when he or she is properly
biologically functioning) his or her central aim is the avoidance of
violent death. Thus Hobbes is able to build his entire natural law
theory around a single good, the good of self-preservation, which is
so important to human life that exceptionlessly binding precepts can
be formulated with reference to its achievement.



The second answer is Aristotelian. The idea here is to reject a
subjectivism about the good, holding that what makes it true that
something is good is not that it stands in some relation to desire but
rather that it is somehow *perfective* or *completing*
of a being, where what is perfective or completing of a being depends
on that being's nature. So what is good for an oak is what is
completing or perfective of the oak, and this depends on the kind of
thing that an oak is by nature; and what is good for a dog is what is
completing or perfective of the dog, and this depends on the kind of
thing that a dog is by nature; and what is good for a human depends on
what is completing or perfective of a human, and this depends on the
kind of thing a human is by nature. So the fact of variability of
desire is not on its own enough to cast doubt on the natural law
universal goods thesis: as the good is not defined fundamentally by
reference to desire, the fact of variation in desire is not enough to
raise questions about universal goods. This is the view affirmed by
Aquinas, and the majority of adherents to the natural law
tradition.



The third answer is Platonic. Like the Aristotelian view, it rejects a
subjectivism about the good. But it does not hold that the good is to
be understood in terms of human nature. The role of human nature is
not to define or set the good, but merely to define what the
possibilities of human achievement are. So one might think that some
things -- knowledge, beauty, etc. -- are just good in
themselves, apart from any reference to human desire or perfection,
but hold that the pursuit of these are only part of the natural law
insofar as they fall within the ambit of human practical possibility.
This view of the good is not much defended -- in part because of
the scathing criticism offered of Plato's view by Aristotle in
the *Nicomachean Ethics* (NE I, 6) -- but it was affirmed
by Iris Murdoch (1970), and forms part of the natural law view
defended by Michael Moore (1982).



None of these answers is without difficulties. While there are
contemporary defenders of Hobbesian moral theories (see Gauthier
1986), there is no one who is on record defending Hobbes's
interesting combination of a thoroughgoing subjectivism about the good
along with an account of a dominant substantive good around which the
moral rules are formulated. The basic reason for this just seems to be
that Hobbes's arguments that the human desire for
self-preservation is such an entirely dominant desire are implausible,
and there do not seem to be any better arguments available. The
Platonic version of the view has struck many as both too
metaphysically ornate to be defensible, on one hand, and as not
fitting very well with a conception of ethics grounded in nature, on
the other. While the Aristotelian version of the view has also been
charged with some of the metaphysical excesses that the Platonist view
allegedly countenances, most contemporary natural law theory is
Aristotelian in its orientation, holding that there is still good
reason to hold to an understanding of flourishing in nature and that
none of the advances of modern science has called this part of the
Aristotelian view into question. (For defenses of such Aristotelian
accounts of the good, see Foot 2001, Thompson 1995, and Thompson
2004.) 


### 2.2 Knowledge of the basic goods



Another central question that the natural law tradition has wrestled
with concerns our knowledge of the basic goods. How can we come to
know these fundamental goods?



Return to Aquinas's paradigmatic natural law position. His
account of our knowledge of the fundamental goods has been understood
in different ways (Murphy 2001, ch. 1). Some have understood Aquinas
as affirming a theory of our knowledge of the fundamental precepts of
the natural law that we can label 'derivationism.' 
The idea here is that we can derive from a metaphysical study of human
nature and its potentialities and actualizations the conclusion that
certain things are good for human beings, and thus that the primary
precepts of the natural law bid us to pursue these things (cf. Lisska
1996). One can imagine a Hobbesian version of this view as well. One
might say that by a careful study of the human being's
desire-forming mechanisms, one can see that there are certain things
that would be necessarily desired by biologically sound human beings,
and thus that the human good includes these items. (Hobbes in fact
produces such arguments at [EL], I, 7.)  While a natural law
theorist might downplay the importance of derivationist knowledge of
the natural law, it is hard to see how a consistent natural law
theorist could *entirely* reject the possibility of such
knowledge, given the view that we can provide a substantial account of
how the human good is grounded in nature: for to show that the human
good is grounded in nature is to show that human nature explains why
certain things are goods, and it is hard to see how one could affirm
that claim while entirely rejecting the possibility of derivationist
knowledge of the human good (see Murphy 2001, pp. 16-17). Some
have thought, echoing criticisms of natural law theory by those
entirely hostile to it, that derivationist theories of practical
knowledge fall prey to 'Hume's Law,' that it is
impossible to derive an 'ought' from an 'is,'
that is, any normative truth from any set of nonnormative truths. The
most that this can show, though, is that the natural law theorist
needs an account of those bridge truths that enable us to move between
claims about human nature and claims about human goods.



It must be conceded, however, that a consistent natural law theorist
could hardly hold that derivationist knowledge of the human good is
the only such knowledge possible. For it is part of the paradigm
natural law view that the basic principles of the natural law are
known by all, and the sort of arguments that would need to be made in
order to produce derivationist knowledge of the human good are
certainly not had (or even have-able) by all. (Recently Jensen (2015)
has offered a thorough defense of a derivationist account that aims to
take such worries into account.) Another way that Aquinas's
account of knowledge of the fundamental goods has been understood
-- and it is an understanding better able to come to grips with
the widespread knowledge of fundamental goods -- can be labeled
'inclinationism.'  On this view, one's explicit
grasp of the fundamental goods follows upon but is not derived from
one's persistent directedness toward the pursuit of certain
ends, which directedness involves an implicit grasp of these items as
good. So human beings exhibit a tendency to pursue life, and
knowledge, and friendship, and so forth; and reflection on this
tendency occasions an immediate grasp of the truth that life, and
knowledge, and friendship, and so forth are goods. The affirmation of
the claims 'life is good,' 'knowledge is
good,' 'friendship is good,' etc. makes intelligible
the persistent pursuit of these ends by rational beings like us.



While inclinationism and derivationism are distinct methods, they are
by no means exclusive: one can hold that knowledge of fundamental
goods is possible in both ways. Indeed, it may well be that one way of
knowing can supplement and correct the other. There may be some goods
that are easier to recognize when taking the speculative point of
view, the point of view of the observer of human nature and its
potentialities, and some that are easier to recognize when taking the
practical point of view, the point of view of the actively engaged in
human life. Indeed, by connecting nature and the human good so
tightly, the natural law view requires that an account of the good
reconcile these points of view.



There are, of course, reasons to be worried about both of these ways
of knowing basic goods -- worries that go beyond general
skeptical doubts about how we could know any normative truths at
all.  Derivationists have to explain how we come to know what
counts as an actualization of a human potency, and have to explain how
we connect these via bridge principles with human goods.
Inclinationists have their own troubles. In particular, they need to
deal with the fact that, even if they are not in the business of
deriving goods from inclinations or identifying the goods precisely
with what we tend to pursue, they take as their starting point human
directedness.   And it has been rightly noted that human
directedness is not always a lovely thing. Power and prestige seem to
be a matter of human directedness -- at least as much so as,
say,  aesthetic enjoyment and speculative knowledge -- but
they do not make it to the natural law theorist's catalog of
goods (though they do appear to be part of the good in
Aristotle's picture; cf. the discussion in Hare 2001, p. 14).
While these difficulties persist for inclinationist and derivationist
accounts of knowledge of the basic goods, they may well be eased if
one affirms both accounts: one might be able to use inclinationist
knowledge to provide some basis for bridge principles between
knowledge of human nature and knowledge of human goods, and one might
be able to use derivationist knowledge to modify, in a non-ad-hoc way,
the objectionable elements of the account that one might be bound to
give if proceeding on an inclinationist basis alone. (Reconciling the
inclinationist and derivationist approaches is a theme in Murphy 2001
and Wall 2010.)



The dialectic between inclinationist and derivationist accounts of
knowledge of the first principles of the natural law is central to
natural law epistemology, but there are other accounts of knowledge of
the natural law that focus on its social dimension. Alasdair MacIntyre
has argued, for example, that the first precepts of the natural law
are to be understood as those that make possible communal inquiry into
the nature of the good: both the positive and the negative precepts
are enabling rules, norms that enable humans to engage in common
pursuit of knowledge of what is valuable. The norms of the natural law
preclude our acting toward other potential partners in inquiry in way
that would undermine the possibility of common pursuit of the good
(MacIntyre 1994, 183-184). To come to know the primary precepts
of the natural law, then, is a matter of coming to know what sorts of
social relationships make possible common pursuit of common goods.




A distinct sort of social emphasis on knowledge of the natural law
asks why we should think of knowledge of the natural law as arising
exclusively or even predominantly either from one's own
immediate rational insight into what is implicit grasped or from some
sort of derivation from the fact that one's own inclinations of
the will have certain determinate objects. One might hold that we have
excellent reason to believe that knowledge of the natural law unfolds
historically. Jean Porter, for example, argues that by close attention
to the various sorts of social structure exhibited cross-culturally,
we can extract the necessary "starting points" (Porter
2005, p. 132) to begin assessing various proposed norms of
action. And Jonathan Crowe emphasizes knowledge of the natural law as
the outcome of the attempt to interpret human practices, and will be
an historically-extended process that will be necessarily an
unfinished task (Crowe 2019, pp. 6-7; there is also discussion of
interpretation of social practices as a means to knowing the natural
law in Murphy 2007).


### 2.3 The catalog of basic goods



A developed natural law theory includes within it a catalog of the
fundamental goods, the basic values upon which the principles of right
are founded. Suppose that we follow at least the inclinationist line,
taking it to be faithful to the natural law idea that knowledge of the
basic goods is widely distributed. Our task then is to provide an
explicit account of those goods implicit knowledge of which is
manifested in human inclination toward certain ends. What are the
goods affirmation of which makes intelligible these inclinations?



It is clear from this way of putting the question that even if natural
law theorists are right that this implicit knowledge is widely
distributed, it would be easy for natural law theorists to disagree in
their catalogs of basic goods. For the task here is that of
formulating propositionally, and in as illuminating a way as possible,
what items need be affirmed as intrinsically good in order to make
sense out of our inclinations. And there are, unsurprisingly,
disagreements in catalogs of basic goods. The goods that Aquinas
mentions in his account include life, procreation, social life,
knowledge, and rational conduct. Grisez 1983 includes
self-integration, practical reasonableness, authenticity, justice and
friendship, religion, life and health, knowledge of truth,
appreciation of beauty, and playful activities (pp. 121-122).
Finnis 1980 includes life, knowledge, aesthetic appreciation, play,
friendship, practical reasonableness, and religion (pp. 86-90).
Chappell 1995 includes friendship, aesthetic value, pleasure and the
avoidance of pain, physical and mental health and harmony, reason,
rationality, and reasonableness, truth and the knowledge of it, the
natural world, people, fairness, and achievements (p. 43). Finnis 1996
affirms a list much like Grisez 1983, but includes in it "the
marital good" (p. 5). Murphy 2001 includes life, knowledge,
aesthetic experience, excellence in work and play, excellence in
agency, inner peace, friendship and community, religion, and happiness
(p. 96). Gomez-Lobo 2002 includes life, the family, friendship, work
and play, experience of beauty, theoretical knowledge, and integrity
(pp. 10-23). Crowe (2019) includes life, health, pleasure,
friendship, play, appreciation, understanding, meaning, and
reasonableness (p. 35).



Aside from the inevitable differences in lists of goods produced by
natural law theorists, there are also more focused debates about the
inclusion of particular alleged goods within the natural law
theorists' lists. Note, for example, that of the lists above,
only Chappell's includes pleasure and the absence of pain.
Whatever else we say here, it seems that common sense is initially on
Chappell's side: what seems more obvious than that pleasure and
the avoidance of pain are basic reasons for action?  The reasons
for rejecting pleasure and the absence of pain from the list of goods
are various: some writers argue, following Aristotle, that pleasure is
not a good in abstraction from the activity in which pleasure is
taken; some that the absence of pain is not a completion or a
fulfillment of human nature, and thus cannot be among the basic goods;
some that the avoidance of pain is simply an instance of some other
basic good, such as inner peace. What this debate illustrates is the
extent to which the formulation of a catalog of goods is not a
straightforward matter. Everyone agrees that one who avoids touching a
hot stove in part to avoid the awful pain has *some reason* to
avoid touching the stove. The difficulty is to bring together our
various sources of knowledge about the good to formulate an account
that explains well precisely why it is that such an act is reasonable.
These sorts of debates reappear with respect to goods like life (is
life intrinsically or instrumentally good?  is merely being alive
intrinsically good, or is life only intrinsically good when one is
enjoying a certain level of vitality?), religion (is harmony with God
really a human good?  is it merely a kind of friendship? 
does its status as a good depend on whether there is a being such as
God?), and what Finnis and Grisez now call the 'marital
good' (is the good of marriage simply an amalgam of various
other goods, as friendship, procreation, rational agency, or is it
really a distinct, analytically separable value?). Thus
Echenique denies that life can be a basic good in the way that
natural law theorists typically take it to be (Echenique 2016);
Cuneo has rejected religion as a basic good (Cuneo 2005, pp.
116-118); and Macedo has argued against the marital good (Macedo
1995).


### 2.4 From the good to the right



Suppose that we were to have in hand satisfactory accounts of natural
goodness and our knowledge of it, along with a rationally defensible
account of the basic goods that are the fundamental reasons for
action. All that we would have so far is the natural law
theorist's account of what we might call minimally rational
action -- action that seeks to realize some good. What we would
not have yet is a full account of right action. For we are frequently
in situations in which there are various different courses of action
that we might pursue, each of which promises to realize some good; are
there no guidelines to which we might appeal in order to show some of
these choices superior to others?  After all, some of even the
most obviously morally wrong actions can be seen to promise some good
-- a robber might kill in order to get the money he needs to
pursue genuine goods -- and the natural law theorist wants to be
able to say why these obviously morally wrong actions are morally
wrong. As we have seen, the paradigmatic natural law view holds that
there are some general rules of right that govern our pursuit of the
various goods, and that these rules of right exclude those actions
that are in some way *defective* responses to the various basic
goods. How, though, are we to determine what counts as a defective
response to the goods?



There are at least three possibilities. One might appeal to a master
rule of right that can be used to generate further rules; call this
the *master rule* approach. One might appeal to a
methodological principle by which particular rules can be generated;
call this the *method* approach. Or one might appeal to some
standard for distinguishing correct and incorrect moral rules that is
not understandable as a method; call this (for reasons we shall see
shortly) the *virtue* approach.



On the master rule approach, the task of the natural law theorist is
to identify some master rule which bears on the basic goods and,
perhaps in conjunction with further factual premises, is able to
produce a stock of general rules about what sorts of responses to the
basic goods are or are not reasonable. While it is far from clear
whether there was a single way that Aquinas proceeded in establishing
moral norms from the primary precepts of the natural law in the
*Summa Theologiae*, John Finnis has argued (Finnis 1998, p.
126) that Aquinas employed this master rule approach: on his view,
Aquinas held that this master rule is the rule of universal love, that
one should love one's neighbor as oneself. This rule bids us to
respond to the good lovingly wherever it can be realized, and from it
we can see that certain ways of responding to the good are ruled out
as essentially unloving. Grisez clearly employs this approach: he
writes that the first principle of morality is that "In
voluntarily acting for human goods and avoiding what is opposed to
them, one ought to choose and otherwise will those and only those
possibilities whose willing is compatible with a will toward integral
human fulfillment" (Grisez 1983, p. 184). This first principle,
Grisez says, contains implicitly within it various "modes of
responsibility" from which particular moral rules can be
derived.



The central difficulty with this employment of the master rule
approach is that of explaining how we are to grasp this first
principle of morality as correct. What is the relationship between our
knowledge of the basic goods and our knowledge of the master
rule?  When Grisez defends his master rule, he writes that its
status is due to a certain function that a first principle of morality
must perform:  "It must provide the basis for guiding
choices toward overall human fulfillment. As a single principle, it
will give unity and direction to a morally good life. At the same
time, it must not exclude ways of living which might contribute to a
complete human community" (Grisez 1983, p. 184). But this
presupposes an awful lot: why should we assume in advance that a
proper response to the basic goods must be one that is oriented toward
a "complete human community"?



On the method approach, by contrast, there is no need for a master
principle that will serve as the basis for deriving some particular
moral rules. The idea here is the natural law theorist needs not a
master rule but a test for distinguishing correct moral rules from
incorrect ones. We know from our earlier consideration of the
paradigmatic natural law view that the test for distinguishing correct
moral rules from incorrect ones must be something like the following:
if a moral rule rules out certain choices as defective that are in
fact defective, and rules out no choices as defective that are not in
fact defective, then it is a correct moral rule. What would
distinguish different employments of the method approach is their
accounts of what features of a choice we appeal to in order to
determine whether it is defective. The knowledge that we have to go on
here is our knowledge of the basic goods. If a certain choice
presupposes something false about the basic goods, then it responds
defectively to them. So a moral rule can be justified by showing that
it rules out only choices that presuppose something false about the
basic goods.



This is very abstract. Here is an example of an employment of this
approach. While Finnis now affirms Grisez's master rule
approach, in his 1980 work he defends various principles of practical
reasonableness without adverting to a master rule. He argues, for
example, that it is always wrong to intend the destruction of an
instance of a basic good (Finnis 1980, pp. 118-123). (So, no
lying, for lying is an intentional attack on knowledge; no murder, for
murder is an intentional attack on life, and so forth.)  Why is
it always wrong to do so?  It would be unreasonable simply to try
to destroy an instance of a basic good, for no further purpose: for
that would treat an instance of a basic good as something that it is
not -- that is, as valueless. And it would be wrong to destroy an
instance of a basic good for the sake of bringing about some other
instance of a basic good: for that would make sense only if the good
brought about were more valuable than the good destroyed, but on
Finnis's view all distinct instances of basic goods are
incommensurable -- none is of more, less, or equal value with any
other. So the rule forbidding intentional destruction of an instance
of a basic good is justified because it rules out only choices that
presuppose something false about the nature of the basic goods. (For a
working out of the method approach, see Murphy 2001, ch. 5.)



The method approach presupposes less of substance about morality than
the master rule approach presupposes. But it requires us to draw upon
an interesting and rich knowledge of the features of the basic goods.
Whether this information is available is a matter for debate. But the
method approach has the advantage of firmly rooting natural law
arguments for moral principles in the goods the pursuit of which those
moral principles are supposed to regulate.



Neither the master rule nor the method approach implies that the
natural law theorist must hold that all right action can be captured
in general rules. The natural law view is only that there are some
such rules. It is consistent with the natural law position that there
are a number of choice situations in which there is a right answer,
yet in which that right answer is not dictated by any natural law rule
or set of rules, but rather is grasped only by a virtuous, practically
wise person. It is, however, open to the natural law theorist to use
this appeal to the judgment of the practically wise person more
widely, holding that the general rules concerning the appropriate
response to the goods cannot be properly determined by any master rule
or philosophical method, but can be determined only by appeal to the
insight of the person of practical wisdom. If it really is wrong in
all cases to tell lies, as Aquinas and Grisez and Finnis have argued,
our grasp of this moral truth is dependent on our possessing, or our
being able to recognize the possessor of, practical wisdom. If such a
person never tells lies, because she or he just sees that to tell lies
would be to respond defectively to the good, then that lying is always
wrong is a rule of the natural law.



It may be true that by the virtue approach we can learn of some
general rules of the natural law. What is more interesting is whether
a defender of the virtue approach would be right to dismiss the claims
of the master rule or method approaches. (For, after all, one might be
able to learn that lying is wrong *either* through moral
argument or through the perceptive insight of practical wisdom.) 
And it does not seem that the defender of the master rule or method
approach should be particularly concerned to discredit the virtue
approach. For if defenders of the master rule or method approach
recognize the existence of a capacity of judgment like practical
wisdom, then it would be strange to allow that it can be correctly
exercised on a number of particular occasions while denying that we
might learn of general rules from observing patterns of its exercise
on various occasions.



One challenge to these various natural law attempts to explain the
right in terms of the good denies that the natural law theorist can
provide adequate explanations of the range of norms of right conduct
for which moral theories ought to be able to provide explanations.
That is, one might allow for the sake of argument the natural law
theorist's identification of some range of human goods, while
denying that he or she can identify, and justify in natural law terms,
adequately concrete modes of appropriate response to those goods. This
challenge cannot be profitably addressed here; what would be required
would be a close examination of the merits of particular natural law
explanations of particular moral norms (a task taken up in, for
example, Grisez 1993). One might also look to recent attempts to apply
the natural law view to pressing contemporary moral problems --
those of research ethics (Tollefsen 2008), economic justice (Chartier
2009), environmental ethics (Davison 2009), business ethics (Gonzalez
2015), the ethics of suicide and euthanasia (Paterson 2015), and
population ethics (Delaney 2016), for example -- as tests of the
fruitfulness of that position.



A more radical critique of the paradigmatic natural law account of the
connection between the good and the right calls into question the very
idea that one can get principles of moral rightness merely from what
constitutes a defective response to the good. According to this
critique, while it is true that one might be able to come up with some
notion of *unreasonableness* by appeal to the notion of what is
defective response to the human goods, the notion of moral rightness
belongs to a family of concepts distinct from that to which the notion
of reasonableness belongs. On this view, moral rightness belongs to
the obligation family, and the concept of obligation is
*irreducibly social*: one is under an obligation only if one is
subject to some sort of demand in the context of a social relationship
(see, for an example of this view from a theological voluntarist
perspective, Adams 1999, pp. 238-241; see, for an example of
this view with a Kantian twist, Darwall 2006). It is part of the logic
of obligation that when one is under an obligation, that condition has
resulted from a demand imposed on him or her by some other party. So,
according to this line of criticism, the paradigmatic natural law view
is unable to show that the natural law is intrinsically morally
authoritative: the precepts of the natural law can be rules that all
of us human beings are *obligated* to obey, that it would be
*wrong* for us to disobey, and that we would be *guilty*
for flouting only if these precepts are imposed upon us by an
authoritative being -- perhaps a being like God.



The intrinsic moral authority of the natural law has been a matter of
debate since Aquinas: it was a central issue dividing Aquinas's
view from those of Scotus, Ockham, and Suarez. It continues to be an
issue between natural law theorists like Grisez (1983) and Finnis
(1980) on one hand and theological voluntarists like Adams (1999) and
Hare (2001) on the other. Natural law theorists have several options:
they can argue against any meaningful distinction between morality and
the reasonable more generally (Foot 2000, pp. 66-80); or they
can embrace the distinction, but hold that on the clearest conception
of the moral that we possess, the natural law account of
reasonableness in action adequately satisfies that conception (Murphy
2001, pp. 222-227); or they can hold that the notion of
'morally right' is so muddled that it should be
jettisoned, leaving in its stead the notion of the reasonable (cf.
Anscombe 1958). It is at present far from clear which of these avenues
of response the natural law theorist has most reason to embrace.