Still, granted that human beings are different in kind (because of the powers of conceptual thought and free choice) from other animals, how do these differences show that human beings are entitled to a specific type of respect? Why should having conceptual thought and being moral agents mean that human beings should be treated with a special kind of respect? The general problem can be expressed as follows. It seems that it is morally permissible to use some things, to consume them, experiment on them for our benefit (without their consent, or perhaps where they are unable to give or withhold consent) but that it is not morally permissible to treat other beings in this way. The question is, where do we draw the line between those two sorts of beings? By what criterion do we draw that line? Or perhaps there just is no such line, and we should always seek to preserve all beings, of whatever sort?
The last option is obviously impossible. We must eat, we must use some entities for food and shelter, and in doing so we inevitably destroy them. When we eat we convert molecules of one nature into another and thus destroy them. Moreover, no one I know of claims that we should not try to eradicate harmful bacteria and viruses (which are forms of life). That is, we should kill harmful bacteria and viruses in order to protect ourselves and our children. And it seems clear that we must harvest wheat and rice for food, and trees for shelter. So, it is permissible to kill and use some entities. A line must be drawn—that is, a line between those entities it is morally permissible to use and consume, and those it is not permissible to use and consume. How can the line be drawn in a non-arbitrary way?
Of course, various criteria for where the line should be drawn have been proposed: life, sentience, rationality, or being a moral agent (the last two come to the same thing). I will argue that the criterion is: having a rational nature, or being a moral agent (in the sense of an being an entity that has the radical capacity to reason and make free choices, though it may take this being months, or even years, to actualize that capacity, or some anomaly may prevent this being from doing so at all, in this life). Thus, every human being has full moral worth or dignity, in virtue of having a rational nature, or in virtue of being a moral agent.
The criterion for full moral worth is not directly membership in the species homo sapiens. If we discovered extra-terrestrial beings of a rational nature, or that some other terrestrial species did have a rational nature, then we would owe such beings full moral respect. Still, all members of the human species do have full moral worth because all of them do have a rational nature and are moral agents, though many of them are not able immediately to exercise those basic capacities. One could also say that the criterion for full moral worth is being a person, since a person is a rational and morally responsible subject.[i]
The other suggestions listed above, I believe, are not tenable as criteria of full moral worth, and, worse yet, often have the practical effect of leading to the denial that human beings have full moral worth, rather than (only) adding other beings to the set of beings deserving of full moral respect.[ii] And so I think it is important to explain how being a person, that is, being a distinct substance with the basic natural capacities for conceptual thought and free choice is a basis for the possession of basic rights. I will also explain how the recognition of such a difference in kind does not presuppose body-self dualism.
Animal welfarists argue that the criterion of moral worth is simply the ability to experience enjoyment and suffering. Peter Singer, for example, quotes Bentham to say that, “The question is not, Can they reason? nor Can they talk? but, Can they suffer?”[iii] Singer then presents the following argument for this position:
The capacity for suffering and enjoyment is a prerequisite for having interests at all, a condition that must be satisfied before we can speak of interests in a meaningful way. . . . . A stone does not have interests because it cannot suffer. Nothing that we can do to it could possibly make any difference to its welfare. The capacity for suffering and enjoyment is, however, not only necessary, but also sufficient for us to say that a being has interests—at an absolute minimum, an interest in not suffering.[iv]
In short, Singer’s argument is: All and only beings which have interests have rights; but all and only beings that can have suffering or enjoyment have interests; therefore, all and only beings that can have suffering or enjoyment have rights.
In the first place, however, it is not true that only beings with feelings or some level of consciousness can be reasonably considered to have interests. It is clear that living beings are fulfilled by certain conditions and damaged by others. As Paul Taylor, who defends a biocentrist view (all living beings have moral worth) explains:
We can think of the good of an individual nonhuman organism as consisting in the full development of its biological powers. Its good is realized to the extent that it is strong and healthy.[v]
We can then say that what promotes the organism’s survival and flourishing is in its interest and what diminishes its chances of survival or flourishing is against its interests. So, while it may be initially plausible to think that all animals have rights because they have interests, it is considerably less plausible to think that all living beings (which include wheat, corn and rice) have rights. But the interest argument would lead to that position.
More importantly, the argument based on interests—whether in behalf of all animals (Singer’s) or in behalf of all living things (Taylor’s)—confuses two issues. The question about who has full worth or basic rights: which entities are ones whose good or fulfillment should we value as goods or fulfillment to which they have rights? It is no answer to this question to show which entities it is true to speak of as having a good or fulfillment. That is, the question is: of which entities should we care about their good in a certain way (as entities with rights to those goods); the question is not which entities have a good, or have interests. To show that a class of entities has a good or has interests does nothing to show that we are morally bound to care for that good, or those interests, at least not to the extent that we would have other people care about our good or interests (which is an expression of the golden rule).
A third point is that the arguments expressed by Singer and Taylor do not actually attempt to establish that nonhuman animals and other living things have moral rights in the full sense of the term. I think it is true of every living being, in some way, that we should not wantonly destroy or damage it.[vi] With sentient beings, whether their life goes well or badly for them will significantly include their pleasure, comfort, or lack of suffering. And so their flourishing includes pleasure and lack of pain (though it also includes other things such as their life and their activities). Yet it does not follow from these points that they have full moral worth or rights.[vii] There simply is no conceptual connection between pleasure and pain on the one hand, and genuine rights, that is, full moral worth, on the other hand.[viii]
However, almost no one actually argues that these beings have full moral rights. Rather, biocentrists argue that all living things merit some consideration, but also hold that human beings are due more consideration (though not, apparently, different in kind).[ix] In effect, instead of actually holding that all living beings (in the case of biocentrists), or all animals (in the case of animal welfarists) have rights, they have simply denied the existence of rights in the full sense of the term. Instead, they hold only that all living beings (or animals or higher mammals) deserve some varying degree of respect or consideration. I agree with this point, but I also maintain that every human being is a subject of rights, that is, every human being should be treated according to the golden rule, and it is absolutely wrong intentionally to kill or intentionally to deprive any human being of any basic, intrinsic good. In other words, I grant that out of sympathy, or perhaps a natural piety,[x] we should take account of the flourishing of living beings, and the pleasures and pains of nonhuman animals. But we are not morally related to them in the same way that we are to other beings with a rational nature, whom (out of fairness) we should treat as we would have them treat us.
But one might argue for animal rights starting from our natural empathy or affection for them (though our natural empathy or affection, notably, does not extend to all animals, for example, to snakes). If one identifies what is to be protected and pursued with what can be felt, that is, enjoyed or suffered, in some way, then one might conclude that every entity that can have pleasure or pain deserves (equal?) consideration. If the only intrinsic good were what can be enjoyed, and the only intrinsic bad were suffering, then it would not be incoherent to hold that sentience is the criterion of moral standing, that is, that every entity with sentience has (some degree of) moral standing. In other words, it seems that one can present an argument for animal rights that begins from natural feelings of empathy only by way of a hedonist value theory. I can think of no other arguments that begin from that natural empathy with, or affection for, other animals.
But hedonism as a general theory of value is mistaken. The good is not exhausted by the experiential—the key tenet of hedonism. Real understanding of the way things are, for example, is pleasurable because it is fulfilling or perfective of us, not vice versa. The same is true of life, health, or skillful performance (one enjoys running a good race because it is a genuine accomplishment, a skillful performance, rather than vice versa). So, as Plato and Aristotle pointed out, hedonism places the cart before the horse.
Our desires are not purely arbitrary: we are capable of desiring certain things while others leave us unmoved, uninterested. So, prior to being desired, the object desired must have something about it which makes it fitting, or suitable to be desired. What makes it fitting to us is that it would fulfill or perfect us in some way or other. Thus, what makes a thing good cannot consist in its being enjoyed, or in its satisfying desires or preferences. Rather, desires and preferences are rational only if they are in line with what is genuinely good, that is, genuinely fulfilling.[xi] So, hedonism is mistaken. It cannot then provide support for the view that sentience is the criterion of full moral worth. Rather, while it is wrong wantonly to damage or kill a plant, still it can be morally right to do so for a good reason. Similarly, it is wrong wantonly to damage or kill a non-rational animal, but it can be morally right to do so for a good reason.[xii] Neither sentience nor life itself entails that those who possess them must be respected as ends in themselves or have full moral worth. Rather, having a rational nature is the ground of full moral worth.
The basis of this point can be explained, at least in part, in the following way. When one chooses an action, one chooses it for a reason, that is, for the sake of some good one thinks this action will help realize. That good may itself be a way of realizing some further good, and that good a means to another, and so on. But the chain of goods cannot be infinite. So, there must be some ultimate reasons for one's choices, some goods which one recognizes as reasons for choosing which need no further support, which are not mere means to some further good.
Such ultimate reasons for choice are not arbitrarily selected. That is, the intrinsic goods are not just what we happen to desire, perhaps different objects for different people.[xiii] Rather, the intellectual apprehension that a condition or activity is really fulfilling or perfective (of me and/or of others like me) is at the same time the apprehension that this condition or activity is a fitting object of pursuit, that is, that it would be worth pursuing.[xiv] These fundamental human goods are the actualizations of our basic potentialities, the conditions to which we are naturally oriented and which objectively fulfill us, the various aspects of our fulfillment as human persons.[xv] They include such fulfillments as human life and health, speculative knowledge or understanding, aesthetic experience, friendship or personal community, harmony among the different aspects of he self, and other basic goods.[xvi]
The conditions or activities understood to be fulfilling and worth pursuing are not individual or particularized objects. I do not apprehend merely that my life or knowledge is intrinsically good and to be pursued. I apprehend that life and knowledge, whether instantiated in me or in others, is good and worth pursuing. For example, seeing a young child drowning in a lake, I immediately apprehend that a good worth preserving is in danger and (it is hoped) jump in to save him. The feature, fulfilling for me or for someone like me, is the feature in a condition or activity that makes it an ultimate reason for action. The question is: In what respect must someone be like me for his or her fulfillment to be correctly viewed as worth pursuing for its own sake in the same way that my good is worth pursuing?
The answer is not immediately obvious to spontaneous, or first-order, practical reasoning, or to first-order moral reasoning. That is, the question of the extension of the fundamental goods genuinely worthy of pursuit and respect needs moral reflection to be answered. By such reflection, we can see that the relevant likeness (to me) is that that they too rationally shape their lives, or have the potentiality of doing so. Other likenesses—age, gender, race, appearance, place of origin, etc—are not relevant to making an entity’s fulfillment fundamentally worth pursuing and respecting. But being a rational agent is relevant to this issue; for, it is an object’s being worthy of rational pursuit that we apprehend and which makes it an ultimate reason for action, and an intrinsic good.[xvii] So, I ought primarily to pursue and respect not just life in general, for example, but the life of rational agents—a rational agent being one who either actually or potentially (with a radical potentiality, as part of his or her nature) shapes his or her own life.[xviii]
In addition, by reflection we see that it would be inconsistent to respect my fulfillment, or my fulfillment plus that of others whom I just happen to like, and not respect the fulfillment of other, actually or potentially, rational agents. For, entailed by rational pursuit of my good (and of the good of others I happen to like) is a demand on my part that others respect my good (and the good of those I like). That is, in pursuing my fulfillment I am led to appeal to the reason and freedom of others to respect that pursuit, and my real fulfillment. But in doing so, consistency, that is reasonableness, demands that I also respect the rational pursuits and real fulfillment of other rational agents—that is, any entity that, actually or potentially, rationally directs his or her own actions. In other words, the thought of the golden rule, basic fairness, occurs early on in moral reflection. One can hope that the weather, and other natural forces, including any non-rational agent, will not harm one. But one has a moral claim or right that other mature rational agents respect one’s reasonable pursuits and real fulfillment. Consistency, then, demands that one respect reasonable pursuits and real fulfillment of others as well. Thus, having a rational nature, or, being a person, as traditionally defined (a distinct subject or substance with a rational nature) is the criterion for full moral worth.
Finally, on this position every human being, of whatever age, size, or degree of development, has equal fundamental dignity and equal basic rights. If one holds, on the contrary, that full moral worth or dignity is based on some accidental attribute, then since the attributes that could be considered to ground basic moral worth (developed consciousness, etc.) vary in degree, one will be led to the conclusion that moral worth also varies in degrees.
It has been recently claimed, against this argument, that the basic natural capacity for rationality also comes in degrees, and so this position (that full moral worth is based on the possession of the basic natural capacity for rationality), if correct, would also lead to the denial of personal equality.[xix] However, it has been shown above that conceptual thought is different in kind, not just in degree, from intelligence found in other animals. Moreover, the criterion for full moral worth and possession of basic rights is not a capacity for conscious thought and choice which inheres in an entity, but being a certain kind of thing, that is, having a specific type of substantial nature.[xx] Thus, possession of full moral worth follows upon being a certain type of thing or substance, namely, a substance with a rational nature, despite the fact that some persons (substances with a rational nature) have a greater intelligence, or are morally superior (exercise their power for free choice in a better way) than others. Since basic rights are grounded in being a certain type of substance, it follows that just having such a substantial nature qualifies one as having full moral worth, basic rights, and equal personal dignity.
An analogy may clarify. Certain properties follow upon being an animal, and so are possessed by every animal, even though not all animals are equal. For example, every animal has some parts which move other parts, and every animal is subject to death (mortal). Since various animals are equally animals—since being an animal is a type of substance rather than an accidental attribute—then every animal will have those properties, even though animals are obviously unequal in many other respects. Similarly, possession of full moral worth follows upon being a person (a distinct substance with a rational nature) even though persons are unequal in many respects (intellectually, morally, etc.).
In sum, human beings constitute a special sort of animals. They differ in kind from other animals because they have a rational nature, a nature that entails having the basic, natural capacities (possessed by each and every human being from the moment he or she comes to be) for conceptual thought and free choice. The position that human beings are animals is fully compatible with belief in the spirituality of the human soul, the human soul’s immortality, and the resurrection of the dead. This difference in kind of human beings from other animals is the basis for full moral worth. Every human being deserves full moral respect, is a being with the right not to be intentionally killed, and a being to whom applies the golden rule.
[i] Boethius’s definition, especially as interpreted by St. Thomas Aquinas, is still valid: “An individual substance (that is, an independently acting substance) of a rational nature.” So, neither a nature held in common by many, nor a part is a person. But every whole human being performing its own actions, including actions such as growth toward the mature state of a human, is a person. See Boethius, De Duobus Naturis, and St. Thomas Aquinas, Summa Theologiae, Pt. I, q. 29, a. 1.
[ii] See Jenny Teichman, Social Ethics: A Student’s Guide (Blackwell, 1996).
[iii] Peter Singer, “All Animals are Equal,” in Thomas Mappes and Jane Zembaty, edd., Social Ethics: Morality and Social Policy, 5th ed. (McGraw-Hill, 1997), 440, quoting Jeremy Bentham, Introduction to the Principles of Moral and Legislation, Chapter 17.
[iv] Peter Singer, “All Animals are Equal,” in Thomas Mappes and Jane Zembaty, edd., Social Ethics: Morality and Social Policy, 5th ed. (McGraw-Hill, 1997), 441. The selection is an excerpt from Peter Singer, Animal Liberation, 2nd ed. (New York Review, 1990).
[v] Paul Taylor, “The Ethics of Respect for Nature,” in James P. Sterba, ed., Morality in Practice, 4th ed. (Wadsworth, 1994), 488.
[vi] Could it be true of every being, living or not? It is hard to see what the good or fulfillment of a non-living being is, since on that level it is hard to know just what are the basic, substantial entities as opposed to aggregates of entities. Thus, when we breathe we convert oxygen and carbon molecules into carbon dioxide molecules—have we destroyed the oxygen in that process or have we only rearranged the atoms in their constitution? It is hard to say.
[vii] Cf. Louis G. Lombardi, “Inherent Worth, Respect, and Rights,” Environmental Ethics 5 (1983), 257-270.
[viii] David Oderberg, Applied Ethics: A Non-consequentialist Approach (Blackwell Publishers, 2000), 101.
[ix] For example, Paul Taylor, op. cit.
[x] Since we are part of a larger material universe we naturally have a feeling of respect for the environment and especially for plants and animals. See David Oderberg, op. cit.
[xi] Thus, the pleasures of the sadist or child molester are in themselves bad; it is false to say that such pleasures are bad only because of the harm or pain involved in their total contexts. It is false to say, “It was bad for him to cause so much pain, but at least he enjoyed it.” Pleasure is secondary, an aspect of a larger situation or condition (such as health, physical and emotional); what is central is what is really fulfilling. Pleasure is not a good like understanding or health, which are goods or perfections by themselves, that is, are good in themselves even if in a context that is overall bad or if accompanied by many bads. Rather, pleasure is good (desirable, worthwhile, perfective) if and only if attached to a fulfilling or perfective activity or condition. Pleasure is a good: a fulfilling activity or condition is better with it than without it. But pleasure is unlike full-fledged goods in that it is not a genuine good apart from some other, fulfilling activity or condition. It is a good if and only if attached to another condition or activity which is already good.
[xii] It is worth noting that nonhuman animals themselves not only regularly engage in killing each other, but many of them (lions and tigers, for example) seem to depend for their whole mode of living (and so their flourishing), on hunting and killing other animals. If nonhuman animals really did have full moral rights, however, we would be morally required to stop them from killing each other. Indeed, we would be morally required to invest considerable resources—economic, military, even—in order to protect zebras and antelopes from lions, sheep and foxes from wolves, and so on.
[xiii] The Humaean notion of practical reason contends that practical reason begins with given ends which are not rationally motivated. However, this view cannot, in the end, make sense of the fact that we seem to make objective value judgments, not contingent on, or merely relative to, what this or that group happens to desire—for example, the judgments that murder or torture is objectively morally wrong. Moreover, the Humean view fails to give an adequate account of how we come to desire certain objects for their own sake to begin with. A perfectionist account, on the contrary, one that identifies the intrinsic goods (the objects desired for their own sake) with objective perfections is able to give an account of these facts. For criticisms of the Humean notion of practical reason: R. Jay Wallace, “How to Argue About Practical Reason,” Mind 99 (1990), 355-387; Christine Korsgaard, “Skepticism about Practical Reason,” in her Creating the Kingdom of Ends (Cambridge: Cambridge University Press, 1996); David Brink, "Moral Motivation" Ethics 107 (1997): 4-32; John Finnis, Fundamentals of Ethics (Washington, D.C.: Georgetown University Press, 1983), 26-79
[xiv] The idea is this: what is to be done is what is perfective. This seems trivial, and perhaps is obvious, but it is the basis for objective, practical reasoning. The question, What is to be done? is equivalent to the question, what is to be actualized? But what is to be actualized is what actualizes, that is, what is objectively perfective. For human beings this is life, knowledge of truth, friendship, and so on.
[xv] This claim, derived from St. Thomas, and has been developed by Thomists and Aristotelians of various types. It is not necessary here to assume one particular development of that view against others. I need only the point that the basic principles of practical reason come from an insight—which may be interpreted in various ways—that what is to be pursued, what is worth pursuing, is what is fulfilling or perfective of me and others like me. For more on this see: Germain Grisez, Joseph Boyle, and John Finnis, “Practical Principles, Moral Truth and Ultimate Ends,” American Journal of Jurisprudence 33 (1988), 99-151; John Finnis, Joseph M. Boyle, Jr., Germain Grisez, Nuclear Deterrence, Morality and Realism (Oxford University Press, 1987), Chapter 9-11. John Finnis, Fundamentals of Ethics (Georgetown University Press, 1983); John Finnis, Aquinas, Moral, Political, and Legal Theory (Oxford University Press, 1998); T. D. J. Chappell, Understanding Human Goods: A Theory of Ethics (Edinburgh: Edinburgh University Press, 1998); David S. Oderberg, Moral Theory: A Non-Consequentialist Approach (Oxford: Blackwell Publishers, 2000); Ralph McInerny, Aquinas on Human Action: A Theory of Practice (Washington, D.C.: Catholic University of America Press, 1992).
[xvi]Once one apprehends various conditions or activities (such as knowledge, life and health, friendship, self-integration, and so on) as really fulfilling and worthy of pursuit, the moral norm arises when one has a choice between one option the choice of which is fully compatible with these apprehensions (or principles) and another option that is not fully compatible with those judgments. The former type of choice is fully reasonable, and respectful of the goods and persons involved, whereas the latter type of choice is not fully reasonable and negates, in one way or another, the intrinsic goodness of one or more instances of the basic goods one has already apprehended as, and recognized to be intrinsically good.
[xvii] The argument presented here is similar to the approaches found in the following authors: Louis G. Lombardi, Op. cit,; Michael Goldman, “A Transcendental Defense of Speciesism,” Journal of Value Inquiry 35 (2001), 59-69; William J. Zanardi, “Why Believe in the Intrinsic Dignity and Equality of Persons?” Southwest Philosophy Review 14 (1998), 151-168.
[xviii] I defend the position that the criterion for full moral worth cannot be an accidental attribute, but is the rational nature, that is, being a specific type of substance, in “The Pro-Life Argument from Substantial Identity: A Defense,” Bioethics 18 (2004), 249-263.
[xix] Dean Stretton, “Essential Properties and the Right to Life,” Bioethics 18 (2004), 264-282.
[xx] In “The Pro-Life Argument from Substantial Identity: A Defense” (Bioethics 18 , 2004), I emphasized that possession of rationality should not be interpreted as an attribute inhering in a thing, but as “being a certain kind of thing, that is, having a specific type of substantial nature” (254). A rational animal (I said) is “a type of substance, and . . . being rational (having the natural capacity for conceptual thought and free choice) is a specific difference, a feature expressing (in part) what the substance is instead of an accidental characteristic.” (256)