This book set out to explore what vulnerability is for humans and for animals, and to establish why and when vulnerability matters from a moral point of view. The first goal was to present a definition of vulnerability for the domain of bioethics which would resolve the conflict in the literature regarding the scope of vulnerability. In particular, I investigated whether vulnerability is, as some have suggested, a property belonging to everyone by their very nature (“universal vulnerability”), or whether it is a property restricted to some individuals and groups in certain contexts who are in need of special protection and additional attention (“situational vulnerability”). I suggested that a viable account of vulnerability should reconcile these two views.

This book has aimed to contribute a more nuanced and detailed understanding of vulnerability to contemporary debates in philosophy, bioethics, and the vulnerability literature in general—that is, an understanding of vulnerability that is free from the difficulties of former definitions. I proposed that vulnerability is a matter of degree: all beings with interests can be considered generally vulnerable, yet some individuals, in certain situations, are more likely to have their interests unfairly considered and to consequently experience wrongful harms and mere wrongs. These individuals and groups should be regarded as particularly vulnerable in this specific context and should be afforded additional attention and special protection to receive what they are due.

The second goal was to trace the ethical implications of situational vulnerability for the domain of (bio-)ethics in general and for the field of animal ethics in particular. That is, a substantial part of the book was devoted to the question of whether animals can be regarded as particularly vulnerable in certain situations or contexts, and to outline the moral implications of situational vulnerability for animals. I thus aimed to fill an important gap in the literature, as animal vulnerability and its moral implications have yet to be examined in-depth and systematically.

I have argued that vulnerability discourse is already established with regard to humans, and fulfills a specific role—that is, to orient our attention toward those individuals and groups in need of special protection and additional attention in specific situations. The description of a group as “particularly vulnerable” in a specific context thus has not only rhetorical force, but also normative weight: it shows that additional attention and potentially even special protection may be needed when dealing with certain groups, as the individuals of these groups run a higher risk of being denied what they are due.

My main suggestion has been that vulnerability discourse, so understood, can fulfill the same role for sentient animals. Indeed, the language of vulnerability can highlight those animals who are in need of additional attention and better protection because they are members of groups who are likely often denied what they are due. Extending the concept of vulnerability to animals, I argued, may positively influence how we think about and treat these creatures, by refocusing our attention on their claims and needs. At the same time, though, we should remain humble about what vulnerability language can achieve. To be sure, vulnerability discourse cannot work miracles; nonetheless, this language can fulfill the same function for animals as for humans—no more and no less.

In the following, I summarize the main results of the book in greater detail, and assess whether the goals set out in the beginning of this book have been reached. In a second step, I discuss several objections one could make against the arguments presented in this book, and offer tentative responses.

8.1 Summary

Chapter 1 introduces the topic of vulnerability language and stresses its importance. Chapter 2 presented three scenarios involving what we would likely deem vulnerabilities: the Tuskegee syphilis study, the separation of refugees’ children from their parents at the border between the U.S. and Mexico, and the BSE scandal in the U.K., which led to the (premature) killing of millions of cattle. The purpose of these case studies was to illustrate that we all probably have an intuitive understanding of what vulnerability means. However, when we attempt to properly define it, we quickly run into challenges, one reason being that vulnerability seems to come and exist in various forms.

In Chaps. 2 and 3, I examined what vulnerability is and suggested how we ought to understand it. I began by presenting two conceptions of vulnerability in the literature: universal or ontological vulnerability on the one hand, and situational or circumstantial vulnerability on the other. Some philosophers and bioethicists assume that vulnerability is a shared property of all humans (and sometimes animals as well)—that is, we are all vulnerable by our very nature. Others understand vulnerability as situational: they stipulate that some individuals are vulnerable in certain situations or contexts and should accordingly be afforded special protection and additional attention. These two conceptions of vulnerability are in tension—at first sight, they seem contradictory and irreconcilable. Indeed, the idea that vulnerability encompasses everyone qua their nature conflicts with the view that vulnerability is a property of only some individuals or groups. Moreover, this conflict has problematic consequences: it remains unclear whether vulnerability is a merely descriptive term, or whether it has normative pull. Not clarifying what vulnerability consists in may result in opposition to the idea that vulnerable beings should be afforded special protection and additional attention. After all, if all beings are vulnerable by their very nature, then how can special protection only for some be justified?

I noted that any convincing account of vulnerability must reconcile these two conceptions: we need a definition of vulnerability which encompasses universal vulnerability, but which can, at the same time, account for the situational vulnerability of some individuals or groups in specific contexts. Furthermore, the definition should be easily applicable to different cases and scenarios—that is, it should be formal and sufficiently general in scope. Finally, it should be able to explain why some vulnerabilities, but not others, are morally relevant and require action.

To achieve this goal, I argued in favor of an explicative definition—that is, a definition that respects some central uses of ordinary language, yet is stipulative about others. In a word, the definition of vulnerability presented in this book is ameliorative, insofar as it does not merely follow ordinary language but rather outlines how we ought to use and understand the concept of vulnerability. Thus, one aim has been to propose a definition of vulnerability which should be used, not necessarily to describe one which currently is used in ordinary language. This ameliorative definition, in turn, should facilitate the identification of those individuals who are situationally vulnerable and thus have a claim to special protection and additional attention. I referred to these individuals and groups as “particularly vulnerable” (or as “individuals with increased vulnerability”) throughout the book.

To arrive at such an account, I closely analyzed the term “vulnerability” along with sets of phrases involving “X is vulnerable to Y.” I concluded that vulnerability ascriptions express that some Y may happen to X. That is, vulnerability expresses that some state Y has a certain likelihood, under certain circumstances, of manifesting itself. I inferred from this that vulnerability is a dispositional concept, concluding that three aspects must be distinguished and accounted for when defining it: the reasons why an object is vulnerable; the conditions under which vulnerability may appear; and the various manifestations of vulnerability.

These distinctions led to the definition of vulnerability presented in Chap. 3: Vulnerable beings are individuals with either welfare interests or agency interests that may be frustrated by the individuals themselves, by external circumstances, or by other living beings. The possession of welfare and agency interests is the reason why a being is vulnerable. These interests may be frustrated by individuals themselves, by external circumstances, or by other living beings—they represent the conditions of manifestation. Finally, the manifestations of vulnerability are justified or unpreventable harm, unjustified harm, and mere wrongs which do not entail any harm. I argued in favor of the view that manifestations of vulnerability are externally caused—that is, vulnerability does not inhere within things or individuals; rather, entities are caused to manifest a certain state by external circumstances or actions, in relation to and in interaction with their environment.

Some manifestations of vulnerability simply cannot be prevented, such as accidental injuries, harm resulting from natural catastrophes, or being attacked by someone who is not responsible for their actions. These incidents all diminish welfare or agency and may result in harm. However, if nobody had the power or ability to prevent these events, then they cannot be considered wrongful harms.

Some manifestations of vulnerability, though, could and should have been prevented. In such cases, individuals experience wrongful harm or mere wrongs without any harm. Regarding wrongs without harm, I described cases in which an individual’s welfare or agency interests are unjustifiably disregarded by another moral agent (e.g., due to prejudices and stereotypes), but where the individual is not actually made worse off. In such cases, the person is wronged although she does not experience any harm. Examples are breaches of confidentiality or disrespect for someone’s autonomous decision-making in the healthcare sector which do not result in any negative consequences, or which may even improve the individual’s welfare. From a moral point of view such actions are wrong, even though they do not necessarily result in harm or make someone worse off.

Furthermore, I can wrong someone without being in her vicinity. In many cases, I have the power to positively or negatively affect a person’s interests even if she is located far away from me. In such cases, I still often have the capacity to influence the course of a situation, for example, if I could assist an individual by providing money or time. Consequently, I may have a duty to justly consider the interests of some individual, even if I do not know her personally. Indeed, distance does not matter, from a moral perspective. If we have duties toward individuals, we are no longer merely talking about their interests—they have legitimate claims.

These considerations allowed me to specify who is particularly vulnerable in certain situations: some individuals are at comparatively higher risk of having their claims intentionally or unintentionally disregarded, overlooked or unfairly considered. As a consequence, they are more likely to incur wrongful harm or mere wrongs. The reasons for these unjustified manifestations of vulnerability may include ignorance of the specific needs of a population (e.g., due to language barriers or lack of interest in the specific group), implicit or explicit biases and prejudices, discriminatory attitudes, conflicts of interest, and so on. The individuals concerned are in need of additional attention and special protection in order to obtain what they are due.

To lower the risk of unjustifiable manifestations of vulnerability, we need to identify those individuals in specific situations who run a higher risk of not receiving what they are due. In practice, this means that we must think about the groups we tend to overlook, neglect, and forget, but also recognize which of their claims we tend to ignore. The question then becomes: When is vulnerability so acute that it warrants special protection and additional attention? Admittedly, this is often a matter of degree, and there may be a gray zone. Nonetheless, in many situations, there are some groups who may more often be victims of stereotypes or who tend to be ignored, forgotten, and overlooked. In these cases, steps should be taken to reduce their risk of incurring unjustified harm and mere wrongs.

I concluded that there is only one type of vulnerability encompassing everyone who has interests. But, depending on the specific situation and the groups involved, vulnerability has different likelihoods of manifestation: a change in setting may render some previously only generally vulnerable individuals particularly vulnerable. The controversy as to whether vulnerability is a property of all or of only some beings can thus be resolved. Any account of particularly vulnerable individuals in specific situations who are in need of special protection and additional attention must be embedded within a broader conception of universal vulnerability.

After these considerations, we can come back to the examples with which I started out Chap. 2, and answer the question of what rendered these groups particularly vulnerable in their specific contexts. The individuals concerned were all members of groups that were (and probably still are) comparatively more likely to be denied what they are due. In the case of the Tuskegee syphilis study, a poor and oppressed group—Black Americans—were enrolled in the study. Among other problems with the study, the participants were not given the necessary information about the study and its aims, nor were they informed about a treatment which became available during the study. The legitimate claims of the men enrolled in the study, as well as the claims of their family members, were unfairly considered due to racist prejudices and attitudes. As for the case of the children separated from their parents at the border between the U.S. and Mexico, the specific interests and basic claims of the children of refugees and immigrants were ignored (e.g., the children were separated from their primary caregivers, and they were not given access to education). Finally, in the case of cattle during the BSE scandal in Great Britain, we can now see that these creatures were wronged in different ways. They had not been given the type of food they needed to thrive (their feed was complemented with meat-and-bone meal), and once the disease outbreak happened, they were summarily killed—isolation and medical treatment were not provided (or even considered), a situation we would find inacceptable in the case of humans. The cattle were treated this way precisely because they were animals: for many people, animals have a merely economic value; their lives do not count for their own sakes. Our treatment of animals is still determined, in many cases, by speciesism—a disadvantageous treatment or consideration of those beings who do not belong to a particular species (Horta 2010).

These considerations reveal an advantage of my account of vulnerability: it is context-sensitive. It is formal enough to be applied across different situations, groups, and even species. In Chaps. 4, 5, 6, and 7, I explored, in greater detail, the potential of my account of vulnerability for animals. I discussed whether the concept can be meaningfully extended and applied to animals and considered what it adds to debates in animal ethics. In Chap. 4, I inquired whether animals can fulfill the conditions of vulnerability ascriptions, contending that sentient animals do possess welfare interests, and that some animals also have agency interests (which can potentially be frustrated). Examples of the latter type of interests are caring for and protecting offspring, advancing in a social hierarchy, and the fact that some animals want to freely choose where they go and with whom they interact. Using the Five Freedoms of Animal Welfare as a basis and further adapting and complementing them, I developed a list of basic welfare and agency interests that most animals likely share

  1. 1.

    an interest in the absence of hunger and thirst;

  2. 2.

    an interest in the absence of suffering (i.e., absence of pain, injury, and disease);

  3. 3.

    an interest in expressing and pursuing normal behavior;

  4. 4.

    an interest in the absence of discomfort, fear, and distress;

  5. 5.

    an interest in self-determination; and

  6. 6.

    an interest in continued existence.

The question is then whether these interests have the status of legitimate claims, involving corresponding duties of moral agents. To this end, I assessed the extent to which animals count from a moral perspective. I defended the view that moral agents owe it directly to sentient animals to take their most fundamental interests into account—these duties are not, for example, owed to their human companions or to humanity in general. Moreover, I maintained that animals’ fundamental interests should be considered in accordance with the principle of equal consideration by those holding power over the satisfaction of these interests: similar interests should have equal weight, regardless of their bearer’s species. I thereby rejected speciesism, a form of discrimination based on species-membership.

In practice, these basic interests of animals have the status of legitimate claims, provided that a moral agent can be identified who has some power over their satisfaction. Consequently, moral agents must take the legitimate claims of animals into consideration by fairly applying the principle of equal consideration—that is, weighting like claims alike. If they fail to do so, the animals concerned may incur unjustified harm. Importantly, these basic claims of animals are not necessarily absolute, nor need they be satisfied in all cases. In some circumstances, they can be outweighed by more important claims. In other words, the claims listed here are pro tanto, rather than pro toto claims.

The remaining chapters applied my definition of vulnerability to three groups of animals, specifically: animals used for food (Chap. 5), research animals (Chap. 6), and wild animals (Chap. 7).

In Chap. 5, I discussed whether using and killing animals for food can be ethically justified, or whether we should deem animals used for food a particularly vulnerable group. In a nutshell, I concluded that animal products which are harmfully produced are often—but not always—morally problematic. As for whether painlessly killing happy animals is morally permissible, I argued that killing animals for food is ethically problematic in developed Western societies which have plant-based alternatives to meat products readily available. Indeed, animals’ claim to continued existence should not be overridden to satisfy a mere gustatory preference. One might think that these arguments result in a “principled veganism”—that is, the view that seeking a vegan lifestyle is morally obligatory. I deny this implication, showing that not all uses of animals are necessarily exploitative: consuming animal products can be compatible with respect for animals’ basic claims, in some cases. Furthermore, I showed that farmed animals’ dependency on humans does not necessarily imply that they are particularly vulnerable: ideally, moral agents are capable of respecting the claims of those who are dependent on them. Finally, I concluded that we should nonetheless recognize many groups of animals commonly used for food as particularly vulnerable, and increase their protection accordingly.

Chapter 6 examined whether research animals should be deemed a particularly vulnerable group, or whether the harm they incur during research should be considered ethically justified. I showed that research animals are not sufficiently protected by currently implemented research guidelines and principles. These research principles are sometimes not respected in practice, and remain insufficient from a moral perspective. As a consequence, a large number of animals can be deemed particularly vulnerable in research settings nowadays: animals’ legitimate claims are more likely to be unjustly considered merely because they are animals. In a word, current animal research practices are often speciesist. I then turned to the question of what animal research that respects animals’ claims would look like. For animal research to be ethical, I proposed, it must respect animals’ basic claims (e.g., bodily integrity and continued existence). This can be done by rendering animal research more similar to research with humans. In this vein, I explored how the requirements of social value, scientific validity, independent review, fair subject selection, favorable risk-benefit ratio, informed consent, and respect for research subjects can be fruitfully applied to animal research.

Finally, in Chap. 7, I turned to the question of whether wild animals should be regarded as a particularly vulnerable group. This topic may have come as a surprise. After all, one may regard the manifold forms of harm encountered by wild animals in their daily lives as unpreventable and thus morally unproblematic, as their origin seems to lie with nature, not with human actions. However, I contended that naturally occurring suffering in the wild is not necessarily justified from an ethical perspective. Wild animals can also hold legitimate claims against moral agents, I argued, although humans often fail to respect or even consider these claims. Many humans directly negatively affect wild animals, or cause them indirect harm without a second thought. In addition, while humans often have the ability to improve the lives of wild animals (e.g., by assisting or rescuing them), we often fail to do so. I supported the view that humans sometimes owe positive duties of assistance to wild animals. This does not necessarily imply that humans have to immediately intervene in nature to stop all forms of harm (e.g., predation), as such interventions would likely come at too high a cost for both humans and animals. Nonetheless, moral agents—individually and collectively—are not exempt from conducting research on how to improve wild animals’ life and health or making efforts to respect wild animals’ basic claims. Furthermore, I proposed that if moral agents violate wild animals’ basic claims without an acceptable justification, then we owe the animals concerned some duty of compensation and reparation. For example, if humans pollute animals’ habitat, then we have a duty to clean and restore it. But, in practice, this rarely happens. Consequently, wild animals can frequently be considered a particularly vulnerable group: their claims seldom receive the attention they are due. Humans are likely to ignore and overlook wild animals’ fates, thinking that they fall outside our moral responsibility. On the contrary, humans must change the way we think about wild animals: if wild animals are considered a particularly vulnerable group, they can hopefully benefit from the special protection and additional attention they need to have their legitimate claims ultimately respected.

Importantly, the focused discussions of these three different groups of animals—animals used for food, research animals, and wild animals—mostly served to illustrate how to apply my account of vulnerability. It is possible, even likely, that other animal groups are particularly vulnerable, in various contexts. Think, for example, about animals in captivity (e.g., in zoos), who cannot live out species-typical behavior due to a lack of space and who depend on humans for their survival. Now imagine that a disaster hits, such as a flood or a war. In February 2022, Russia invaded Ukraine. This event was not only devastating to humans (it led to the largest refugee crisis in Europe since the Second World War), but it has also brought enormous suffering to millions of animals. While many Ukrainians fled their homes with their companion animals (such as cats and dogs), countless other animals had to be left behind. The situation is likely dire for animals in barns, research laboratories, and zoos. These animals depend on human care for their survival and well-being, yet buildings with animals were often bombarded, leaving animals buried in rubble or burned in fires. Some zoos ran out of food for their animals, while others tried to evacuate animals to neighboring countries. In war, not only are certain human groups particularly vulnerable (e.g., the elderly and the physically impaired who cannot easily flee), but also many groups of animals: their fates tend to be forgotten, overlooked, and denied due consideration. However, if animals count morally for their own sake, then they should also count in times of crisis and be considered for humanitarian rescue actions (Milburn and van Goozen 2021; Singer and Todorchuk 2022). By framing not only humans but also some groups of animals as particularly vulnerable in conflict situations, we raise awareness about their plight and their legitimate moral claims.

Various steps can be taken to lower the risk of unjustified manifestations of vulnerability. Recall the examples in the beginning of Chap. 1 regarding vulnerabilities during the COVID-19 pandemic: healthcare providers, children, and people who lost their income due to a lockdown. What we should do about these individuals’ risk of incurring unjustified harm or mere wrongs depends on their specific situation and which of their claims are likely to be ignored or unfairly considered. Since vulnerability is context-dependent, so must responses to vulnerability be determined on a case-by-case basis. Special protection and additional attention can require different kinds of actions and measures, depending on the situation. In the case of healthcare providers, personal protective equipment must be organized to protect them against COVID-19. In the case of school children deprived of access to education because of the pandemic, online education must be provided. And in the case of people losing their income because they are obliged to stay at home, monetary compensation may be needed.

In the case of animals, a major reason for their being at risk of having their interests unjustly considered is the influence of speciesist prejudices and attitudes. Therefore, a first general step toward diminishing the manifold wrongs animals are likely to incur would be to educate people about speciesism and the precarious situations of many animals (whether under human care or in the wild). More attention should be paid to their claims, so that they can ultimately receive what they are due.

Following this overview of the book’s main arguments and ideas, I can assess whether the account of vulnerability presented here fulfills the conditions outlined at the beginning. I submit that it does resolve the conflict in the literature regarding the scope of vulnerability. Indeed, the definition of particularly vulnerable individuals in need of special protection is embedded in a broader conception of vulnerability—that is, vulnerability as a property of all beings with certain types of interests. Furthermore, since my definition is both formal in scope and context-sensitive, it can be applied to different domains, such as medical research, healthcare, and humanitarian crises. Moreover, as discussed, it can be extended to various groups of animals. Describing specific animal groups as particularly vulnerable turns our attention toward their fates and reminds us that we should do something to help or protect them. Finally, by distinguishing among different manifestations of vulnerability, I showed why some vulnerabilities require actions (such as in the form of special protection and additional attention), while others do not: some types of harm are morally unproblematic or simply unpreventable; others could—and should—be prevented.

8.2 Objections and Outlook

Some questions may have remained unanswered so far, and some potential challenges and objections to my account of vulnerability may still be open. I address some of them here.

First, one might object that the definition of vulnerability proposed in this book is eliminativist: insofar as it can be reduced to other concepts and terms, it is not substantive or explanatory in its own right. Be that as it may, this objection is not particularly problematic. Even if we reduce the notion of increased or particular vulnerability to other terms or expressions, such as “increased likelihood of having one’s legitimate claims disregarded” and “being at higher risk of incurring unjustified harm,” the concept of vulnerability can still fulfill an important role and function—namely, highlighting those individuals in need of more attention and special protection, in specific contexts. The crucial function of vulnerability discourse is thus to “serve as a very useful means of marking something out for special attention” (Wrigley 2015: 485). This is a rather pragmatic function: vulnerability language serves as a type of warning or signal and points us toward those in need of special protection and additional attention. Moreover, the account of vulnerability proposed here does not need to cover all that we mean by vulnerability in everyday language. As outlined earlier, my aim has been to put forward an ameliorative account of vulnerability—that is, to suggest how we ought to understand vulnerability, rather to describe how the term is commonly used.

Another potential concern with my account of vulnerability is related to priority-setting. It is important to note that vulnerability does not necessarily imply priority. For instance, during the COVID-19 pandemic, there were often not enough hospital beds, medication, and healthcare professionals to treat all the patients. From an ethical viewpoint, we should prioritize those patients who are most likely to survive thanks to medical treatment and who are at the same time likely to die without treatment (Singer 2011: 205). However, this does not necessarily mean that the patients in question are particularly vulnerable. The particularly vulnerable beings in a specific situation are those whose claims we tend to forget, overlook, or disregard. As a consequence, they should be afforded special protection and additional attention. Yet they do not necessarily need to be prioritized for medical treatment, for example.

As shown throughout Chaps. 5, 6, and 7, not only humans but also many animals can be deemed particularly vulnerable in specific situations and contexts. The possibility of extending vulnerability discourse to animals in general might arouse skepticism. As Carol Levine et al. noted in the case of humans, “[i]f everyone is vulnerable, then the concept becomes too nebulous to be meaningful” (Levine et al. 2004: 46). If we extend the concept of vulnerability to animals, as suggested here, this problem becomes even more acute: Will the concept of vulnerability become void and meaningless if we extend it to animals by describing them as particularly vulnerable and in need of special protection and additional attention?

Two points are noteworthy here. First, who is particularly vulnerable in a specific situation is context-dependent. Not all groups who, at some point, qualify as particularly vulnerable remain so at the same time and in the very same situation. This is a specific advantage of my formal and context-sensitive account of vulnerability. Second, and more importantly, if many groups of humans and animals are particularly vulnerable, this does not indicate a weakness within the concept of vulnerability; rather, it points us to a problem with how certain groups of humans and animals are likely to be treated. Indeed, prejudices and stereotypes are deeply entrenched in many societies, and as a consequence, many groups are forgotten, overlooked, or willfully ignored.

Animals can suffer from the very same mechanism: speciesist prejudices are highly prevalent in most societies. Many humans are far from treating animals as they should be treated (with the exception of some domesticated animals in some societies). Therefore, most groups of animals are likely to not be given what they are due. The problem, then, is not that the concept of vulnerability is too broad—the problem is that widespread speciesist practices deprive so many animals of their due. The more we respect the basic claims of domesticated animals, research animals, and wild animals, the less vulnerable they will become. In turn, our attention will probably have to switch to other groups and species which remain particularly vulnerable in specific situations: animals who are regarded as mere nuisances, disease-carriers, or pests and thus often incur many forms of morally problematic harms; animals who may be forgotten or ignored during disasters; and animals who will become victims of climate change.

What can we do to reduce vulnerability? The more we take concrete steps to diminish implicit and explicit biases and the more we carefully analyze certain situations to identify those individuals and groups who are at a higher risk of incurring unjustified forms of harm and wrongs, the more we reduce the risk of unjust manifestations of vulnerability in the case of humans and animals.

While currently many, if not most, animal species can be considered particularly vulnerable, this situation will change as more animals are given their due. If we truly respect animals’ basic claims without any speciesist prejudices and attitudes, fewer groups of animals will be particularly vulnerable. The concept of animal vulnerability can therefore unfold its true force and potential once we start to treat more animals as we should—commensurately with what they deserve.