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Bangladesh Journal of Bioethics 2016; 7(3): 23-33 

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Original Article 

 

Existence and Needs: A case for the equal moral considerability of non-

human animals 

 

Yamikani Ndasauka1 and Grivas M. Kayange2 

1. Department of Philosophy, University of Malawi, Malawi, Email: yndasauka@cc.ac.mw 

2. Chancellor College, University of Malawi, Malawi, Email: gkayange@cc.ac.mw 

 

Abstract: This paper reflects on the question, “Is there a sound justification for the 

existential view that humans have a higher moral status than other animals?” It argues that 

the existential view that humans have a higher moral status than animals is founded on a 

weak and inconclusive foundation. While acknowledging various arguments raised for a 

common foundation between human and non-human animals, the paper attempts to establish 

a common ground for moral considerability of human and non-human animals. The first 

common foundation is based on the existential notion of being in the world, which is 

common for both human and non-human animals. The second idea is based on the common 

desire to actualize different needs. The paper demonstrates these common foundations by 

referring to Heidegger and Abraham Maslow’s hierarchy of needs. 

 

Keywords: Animal rights, existentialism, needs, bioethics, moral consideration 

 

Introduction: Since the onset of human civilization, humans have viewed non-human 

animals as inferior on the hierarchy of being and have hence treated non-human animals as 

instruments for promoting the welfare of humans. It is only in the past century that this 

position has received serious critical attention and has been challenged by an increasing 

number of scholars. From the distant past, and still dominant currently, scholars such as 

Aristotle, Aquinas, Descartes, and Kant have held the view that only humans have moral 

standing and moral agency and hence are the only species worth moral consideration. For 

instance, Immanuel Kant, considered one of the greatest thinkers in philosophy, in his 

discourse on whether animals have a moral status to foster the possibility of animal rights, 

believed that animals have no moral status and rights. For Kant, in a section titled Of Duties 

Towards Animals and Spirit, the only way to consider animals for morality is through indirect 

duty – duty directed at other humans only through moral treatment of animals1. 

 

The whole of this debate emanates from the idea that human and non-human animals are 

essentially different. Numerous views have been provided to underscore the weakness of this 

view2. This paper seeks to add to this debate by attempting to find the common themes that 

run through the human and non-human worlds. Specifically, this paper advances two 

arguments, an argument from existentialism and an argument based on the hierarchy of needs 

to demonstrate how both human and non-human animals participate and seek to fulfill certain 

aspirations as their definitive elements. To achieve this, the paper has three sections. In the 

first section, the paper expounds on the common view that regards humans as having higher 



Bangladesh Journal of Bioethics 2016; 7(3): 23-33 

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moral status than non-human animals. The paper then draws arguments that have been 

previously advanced against this view to show that this common view is unfounded and lacks 

merit in a number of considerations. Then finally, the paper presents its main arguments, 

drawing evidence from science and philosophy to show that in fact human and non-human 

animals have a lot in common and that they all are worth moral consideration. 

 

Existentialist justification of humans’ higher moral status: The existentialist argument 

justifying the supposed higher moral status of humans may be traced in both the Greek and 

Judeo-Christian (traditional) understanding of existence and in modern existentialism, which 

reached its climax in the 19th and 20th centuries. Determination of higher moral status 

between non-human and human animals was founded on the exposition of the link between 

essence and existence. Essence referred to “what it is” (it is the definition of a thing) and 

existence meant “that it is” (to be). The difference between the traditional approach and the 

modern existentialist approach lies in the explication of existence. In traditional perspective, 

explication of existence departs from the objective consideration of essence, which is 

regarded as the primary element that determines everything that can be said about existence. 

It is the essence of a thing that determines its status and role in the world. In modern 

existentialism, explication of existence builds on a subjective view, where existence is given 

preference as coming before the essence of a thing3 4 5. This link is explained depending on 

either an atheist version of existentialism, which excludes God in existence (Jean-Paul Sartre 

and Simone de Beauvoir)6 or on one that accommodates God (Karl Jaspers and Gabriel 

Marcel). In the paragraphs that follow, we discuss arguments that support the higher moral 

status of humans in the Greek and Judeo-Christian tradition and modern existentialist 

versions. 

 

The first argument used to justify that humans have a high moral status than other animals is 

based on the famous Aristotelian claim that the essence/definition of a human being is “a 

rational animal”7 8. Rationality (form) is therefore a defining element responding to “what it 

is”. In his ontological hierarchy of the soul, Aristotle classifies the soul into three forms, 

namely, vegetative soul, appetitive soul, and rational soul. Vegetative soul describes the 

nutritional needs of all living beings. This is the basic category of the soul and there are some 

living things such as plants that only belong to this category. Appetitive soul is responsible 

for emotions and feelings. This category consists of all animals including humans. The 

rational soul is the highest category that includes all human beings. A human being is hence 

regarded highly due to the claim that he or she has nutritional, appetitive as well as rational 

aspects9 10. 

 

In addition to the context of existence, the superiority of humans is extended to morality. By 

having and operating with reason, moral discourse is possible only among human beings. For 

example, Descartes who developed further the centrality of rationality (of course he didn’t 

want to consider rationality as given, but wanted a scientific foundation for understanding 

everything), stressed that every possible form of knowledge is founded on reason, which 

accords humans the ability to act or engage in moral discourse and not other animals who 

lack reason11. According to Descartes, there are two kinds of entities: physical entities and 



Bangladesh Journal of Bioethics 2016; 7(3): 23-33 

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mental entities. Although things in the natural world are closely associated with physical 

bodies, it is only humans that are not identical with their bodies. Rather, they are identical 

with their souls, or the immaterial, mental substance that constitutes their consciousness. 

Descartes believed that human beings have two characteristics that accord them moral worth, 

namely, the complexity of their behaviour/actions and speech. Speech (language) is 

mentioned because it is associated with rationality (thought is expressed through language). 

However, animal behaviour does not require this kind of assumption; besides, Descartes 

argued, “it is more probable that worms and flies and caterpillars move mechanically than 

that they all have immortal souls”12. 

 

The second argument justifying the higher moral status of humans is that the essence of a 

human being is characterised by his or her status of being an image of God. This comes from 

the biblical understanding that God created humans just like other living and non-living 

things but what defines them is the status of being images of God. In Genesis 1:26-30, the 

essence of a human being precedes his or her existence and his or her superiority gets its 

supporting arguments. In verse 26, the bible indicates: “Then God said, ‘Let us make 

mankind in our image, after our likeness, so they may rule over the fish of the sea and the 

birds of the air, over the cattle, and over all the earth, and over all the creatures that move on 

the earth’”. The creation of an individual human being is therefore seen as a situation 

(existence) that instantiates the image of God. Thomas Aquinas commented further on this in 

the following passage: 

 

I answer that, since man is said to be the image of God by virtue of his intellectual 

nature, he is the most perfectly like God according to that in which he can best 

imitate God in his intellectual nature. Now the intellectual nature imitates God 

chiefly in this, that God understands and loves Himself. Wherefore we see that the 

image of God is in man in three ways. First, in as much as man possesses a natural 

aptitude for understanding and loving God; and this aptitude consists in the very 

nature of the mind, which is common to all men. Secondly, inasmuch as man 

actually and habitually knows and loves God, though imperfectly; and this image 

consists in the conformity of grace. Thirdly, in as much as man knows and loves 

God perfectly; and this image consists in the likeness of glory13. 

 

From verse 28-30, humans are given authority to rule over all the other creatures (including 

animals). The superiority of man flowing from this essence (image of God) is twofold. First, 

humans are superior because they are created in the image of God and no other animal 

instantiates this essence. This image is explained in Aquinas with reference to the intellectual 

nature of a human being. Intellect/reason is the nature of God given that God is in some 

respects defined as Logos which refers either to reason or word. God is regarded as perfect 

reason and has different attributes in the Judeo-Christian perspective such as 

omniscience/being all-knowing. By possessing reason, humans are also expected to have 

attributes similar to God’s. Second, superiority entails authority that man was given over all 

other animals. 

 



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Furthermore, the dignity of human beings is explained as following from the dignity of the 

creator. God created all human beings out of his love, and they have unalienable dignity. 

Morality in this context is instructed by God who gave a code of conduct in line with his 

goodness and demanded that all human beings follow/practice it for their own good. Moral 

consideration is therefore seen as following from God. 

 

The third argument justifying the higher moral status of humans may be traced in 

existentialism with respect to existence and essence. While the traditional conception of 

existence and essence reflected on rationality and the image of God as given in the 

understanding of humanity, existentialists of the 19th and 20th centuries argued against this 

position and departed from the consideration of the meaning of being (Heidegger; Sartre). 

Essence in existentialism is an outcome of the subjective experience of an individual in the 

world (essence comes from “to be”). According to Sartre, “thrown into an open-ended 

existence, our essence — who we really are — will be the sum total of all our actions and 

responses to the circumstances in which we find ourselves”14. Essence is therefore what an 

individual human subject lives (experiences) in a particular environment. This fundamental 

doctrine of the existentialists is summarised in Sartre’s expression that “existence precedes 

essence”. Commenting on this expression, Sartre wrote: 

 

What do we mean by saying that existence precedes essence? We mean that man 

first of all exists, encounters himself, surges up in the world – and defines himself 

afterwards. If man as the existentialist sees him is not definable, it is because to 

begin with he is nothing. He will not be anything until later, and then he will be 

what he makes of himself15. 

 

The existentialists argue that what makes humans different from other animals or things, is 

their capacity not only to be but also the ability to subjectively reflect on their own and other 

properties (conscious beings). Humans possess the potential of giving meaning to things and 

themselves as they are thrown in the world. For example, a human being and a dog can sit on 

a stone, but the difference is that a dog will not have a subjective experience of reflecting on 

this stone and produce meaning but a human being can. For this reason, Sartre argued that 

other entities such as animals exist in themselves (etre en soi) and this is what they are 

(essence), but human beings go beyond this. The potential to go beyond this aspect resides in 

the fact that human reality exists in itself and for itself (etre pour soi). The existence in itself 

will make humans similar to all other animals but for itself requires the active experience of 

self-consciousness as being in the world. 

 

The difference between human beings and other objects may be further clarified based on the 

understanding of the existentialist argument that there are different modes of being. 

Heidegger discussed the difference between the existence of humans and other modes such as 

zuhanden and vorhanden. Zuhanden refers to ready-to-hand meaning that something is 

available. These are instruments that are defined by a society and whose properties are 

determined by their usage in a particular society. These apparently get their essence not on 

their own but are given by the community/society where they are utilised. Vorhanden refers 



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to objects of perceptual experience following from norms that govern perceptual givenness of 

an object. These apparently have their essence as determined by human scientific elaboration. 

The zuhanden and vorhanden can be true for all things, animals and human subjects but the 

speciality of humans consists in their subjective capacity to articulate meaning of these 

modes of being. For instance, humans have the subjective capacity to coordinate various 

properties in their actions/experience such as the colour of their physical appearances, the 

system of their beliefs and their belonging to a certain race. They go beyond (transcend) mere 

instantiation of properties in their lives as they willingly and consciously provide further 

interpretation and meaning. 

 

Against the existentialist justification of humans’ higher moral status: Does rationality, 

the image of God, and humans’ subjective existence (reality to exist for itself/etre pour soi, 

self-meaning and choosing what one wants to be in the world) justify that humans have a 

higher moral standing than non-humans? In the following paragraphs, we argue against the 

existential justification of humans’ supposed higher moral status. 

 

Firstly, the existentialist emphasis on human higher moral status due to their claimed unique 

potential for being rational, conscious beings capable of providing meaning to their own 

actions and being, fails to take into consideration the distinction between moral agency and 

moral standing. The rational element of human beings accords them moral agency, however, 

this does not necessarily exclude animals as beings with moral standing16. Whilst moral 

agency pertains to the ability to make sound moral judgments, moral consideration pertains to 

ability to receive and react to moral treatment, consideration and participation in the moral 

community, which is not defined in terms of the intrinsic properties that beings have, but in 

terms of the important social relations that exist between beings17. With this understanding, 

non-human animals have, since time immemorial, been part of human social relations. More 

recently, studies have cemented this claim by positing that animals not only possess and 

develop social relations among themselves and even with humans, but they also have the 

capacity for “cumulative culture” – the ability to build up knowledge over generations. A 

study by the French National Center for Scientific Research (CNRS) and the University of 

Edinburgh found that, “like humans, baboons have the ability to transmit and accumulate 

changes over ‘cultural generations’ and that these incremental changes, which may differ 

depending on the chain, become structured and more efficient”18. 

 

Furthermore, rationality is an obscure concept to the point that even when applied to humans 

it leads to the exclusion of some classes and individuals as irrational. For instance, great 

thinkers such as Hume, Immanuel Kant, Hegel, and Ley Bruhl have once fallen into the trap 

of categorising Africans as irrational (lacking the rational soul). Of course, modern 

existentialism managed to avoid this problem with the insistence of human essence following 

from human experience in the world. Nevertheless, the same concept though not explicit is 

central in providing meaning. The third problem is that rationality, while defined as 

separating humans from other animals, is not definitive for existence. In Aristotle, existence, 

while starting from the nutritive element, matures and becomes evident in appetites where it 

is directly connected with desire. This desire becomes an explanation of purposive 



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behaviour19. 

 

Secondly, the Judeo-Christian argument based on God’s creation falls short as a justification 

for humans’ higher moral status as compared with animals20. There are two related problems 

connected to this, namely, the epistemological and ontological problem of the existence of 

God. The ontological problem regards the possibility of developing a logical argument that 

proves the existence of God as a necessary being and creator of superior human beings and 

other animals. Theologians and philosophers such as Anselm of Canterbury, Thomas 

Aquinas, and Leibniz have in vain attempted to establish arguments supporting the existence 

of God. For example, the ontological argument of Leibniz tried to establish the existence of 

God departing from the idea of a perfect being to the existence of such as being21. This 

argument failed because the existence of an idea of a perfect being does not necessarily imply 

existence. Similarly the five proofs of God’s existence by Thomas Aquinas are well known to 

have failed to prove God’s existence. The related epistemological question regards the 

possibility of “certain knowledge” with regards to the existence of a being known as God. 

The problem has roots in the possibility of knowledge beyond sense experience. This 

problem of founding moral considerability on the existence of a being beyond this physical 

world was worsened further by the Kantian epistemological response that it is impossible for 

human beings to know things beyond sense experience (Noumena). It is only the intellectual 

categories that give humans the possibility of what can exist in the phenomenal world. 

Although Kant did not intend to remove God from the possibility of existence, a general 

tendency of atheists and other thinkers has been that of ignoring the discourse on God. 

 

The problem of establishing convincing argument for the existence of God (ontology) and the 

provision of convincing evidence (epistemology) have led to three groups of thinkers. The 

first group is that of atheists who have completely eliminated the existence of God in absence 

of knowledge. The second group has decided to still maintain the existence of God. The last 

group has decided to remain neutral and indicate that they cannot conclusively know whether 

God exists or does not exist (agnosticism). Based on the existence of these three conflicting 

positions, basing the superiority of humans on the Judeo-Christian belief in the existence of 

God becomes problematic. Due to lack of scientific evidence with respect to the knowledge 

and existence of God, it is reasonable to hold the view of humans’ higher moral status than 

other animals based on the argument of creation and God. 

 

Thirdly, the existentialist attribution of a human being as different from non-humans because 

of its being for itself also fails in two ways. Firstly, there is no convincing scientific evidence 

supporting the fact that only humans experience etre pour soi and that non-humans 

experience only etre in soi. In fact, animals cannot be reduced to only possessing a set of 

nutritive and appetitive elements given that humans cannot with certainty claim knowledge of 

the cognitive experience of animals just depending on experiments. Cognition, which plays 

an important role in etre pour soi, requires a personal experience of being a cognitive animal. 

For instance, a human can only claim that he or she is a doubting things because of personal 

experience of doubting as it was in Descartes. Is it probable to claim that this experience does 

not occur in animals? Are animals deprived of personal experience? Existentialism even in its 



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19th- and 20th-century forms falls short because of a lack of adequate understanding of how 

non-humans become aware of their being in the world. There is no convincing argument to 

this effect apart from going back to the categorisation of human beings as rational animals, a 

point that can contradict the core of modern existentialism which is human meaning 

following from experience in the world. Secondly, although the distinction between humans 

and animals as shown above is problematic, there is also a moral problem that leads us to a 

form of utilitarian/instrumentalist ethics. This follows from the idea that a human being 

creates his or her essence through actions and choices (the way of existing). Human beings 

are conscious of objects, values, meaning, etc. as they construct their essence in the world. 

Morality in this context becomes a creation of human beings to serve man’s needs. This is 

often the case in those existentialist philosophers who exclude God in their idea of existence 

and its finality (Sartre; Simone de Beauvoir). 

 

Equality of moral status between humans and animals: The question of the moral status 

of non-human animals and humans should be based on common moral consideration grounds 

instead of what is assumed to differentiate them. We hold that human and non-human 

animals share numerous attributes, more than the attributes they differ on. The shared 

attributes range from physical to psychological dispositions. To this end, we argue that there 

is an existential common ground for both human and non-human animals qualifying them as 

worth of equal moral consideration. There are two important aspects that demonstrate this 

common existential ground. 

 

The first idea springs from an ontological consideration of being in the world. Both humans 

and animals find themselves in a state of being in the world. Although Heidegger in his 

existentialism focused more on human subjects who are conscious of being there/their 

being22, we are arguing that animals also find themselves in this world and they are conscious 

of their being in their own way. In spite of this, the ontological consideration is difficult to 

establish as a strong case given that it is hard for humans to understand how animals 

experience their being in the world. It is only recently that some studies have begun to 

establish some elements of rationality, which only humans were thought to have. This gives 

an interesting panorama for exploring the possibility of self-awareness of animals as being in 

the world similar to what happens in human beings. For instance, Lori Marino and Christina 

Colvin23 note that pigs are mentally and socially similar to dogs and chimpanzees. They 

write: “what is known suggests that pigs are cognitively complex and share many traits with 

animals whom we consider intelligent”24. Another study found that lowly pigeons provide 

insight into how young children acquire and learn language. Researchers studied pigeons’ 

ability to name and categorize different objects and found that, like children, pigeons engage 

in a type of associative learning to learn new words. In an interview with The Huffington 

Post, Edward Wasserman said: 

 

Our main thesis is that associative learning may underlie the acquisition of complex 

behaviours, including human language […]. [I]f so, then our view of human 

language as altogether unique may need revision [...]. What we learn from studying 

a model animal like a pigeon may not only point to important interspecies parallels, 



Bangladesh Journal of Bioethics 2016; 7(3): 23-33 

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but also help us find ways for more effectively teaching children language, 

especially children with language disorders25 26. 

 

These studies show numerous cognitive abilities that inform the common experience between 

human and non-human animals, which may indicate that animals may also be conscious of 

their being. 

 

The second idea comes from the understanding that both human and non-human animals 

have needs, which they live and seek to satisfy. Abraham Maslow proposes a hierarchy of 

needs consisting of basic needs, psychological needs, and self-fulfilment needs27. Among the 

basic needs, there are physiological needs (food, water and shelter) and safety needs. Among 

the psychological needs, there is the need to belong (make friendships and love) and the need 

for self-accomplishment. Finally, under self-fulfilment, there is self-actualization and 

creativity. A closer look at these needs reveals the common search and desire both human and 

non-human animals have to fulfil and satisfy these needs. 

 

With regard to basic needs, both human and non-human animals require food and water for 

survival. Non-human just like human bodies demand and require important nutrients for 

continued existence in this world. Absence of these nutrients threatens the existence of all 

living beings. In addition, shelter is a fundamental need for many species, including humans, 

given that shelter shields their bodies and protects them from harsh weather conditions as 

well as adversaries. Both human and non-human animals have developed an inclination to 

defend their lives and those of loved ones from outside attack. Just as humans develop 

strategies for protecting life, non-human animals also have defence strategies against their 

enemies. A simple example is when a cow is being slaughtered; he or she will generally try to 

defend his or her life, although more often than not humans overpower the animal. Further, 

researchers have observed scouting behaviour in bottlenose dolphins, in that an individual 

dolphin may investigate novel objects or unfamiliar territories and alert the whole group28. 

All this justifies that the basic needs of human and non-human animals are similar. 

 

With regard to psychological needs, recent studies have shown that different animals have a 

deep sense of compassion and care for their children and sometimes care for each other. For 

example, a study on dolphins has shown how they care for their young ones with a lot of 

affection. According to SeaWorld29, dolphins exhibit different social behaviours that mirror 

human social interaction. Bottlenose dolphins aid ill or injured dolphins. They stand by and 

vocalize, or they physically support the animal at the surface so he or she can breathe. 

Similarly, domesticated dogs and cats also show the need for care and friendship as they 

relate with their caregivers (humans) and among themselves. 

 

The desire for self-fulfilment is demonstrated in some animals that show high levels of 

creativity and cognitive functionality. For instance, most recently, researchers found that 

ravens demonstrate high cognitive functionality comparable with that of apes, which have for 

long been studied and found to possess cognitive functions comparable with those of humans. 

It is reported: “Comparative data gives us insights about the building blocks of higher 



Bangladesh Journal of Bioethics 2016; 7(3): 23-33 

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cognition as well as the relationship between various brain measures and the cognitive 

performance”30. Further, these highly intelligent birds are also known for such evolved 

behaviours as using tools, forming social groups and recognizing faces31. These forms of 

creativity and high cognitive functions demonstrate the shared dispositions between human 

and non-human animals. 

 

The argument from needs ought to be understood within the existential argument for the 

equal moral consideration of non-human animals. As we have argued, rational and/or speech 

abilities in humans and non-human animals are existentially incomparable. Although some 

scientific studies have been undertaken to measure and assess non-human animals’ ability of 

self-consciousness, rationality and speech, the studies are in infancy and some results 

inconclusive. 

 

Conclusion: In this paper, we have argued that the rationale for the existential view that 

humans have a higher moral status than other animals is not adequate, and we have 

demonstrated the weakness of the claim and also the myriad problems that have resulted from 

holding and promoting such a view. We have proposed that, instead of striving to identify 

distinguishing elements between human and non-human animals, it is much better to focus on 

the elements that reveal striking similarities between the species. The similarities that we 

have advanced in this paper, the existential and needs theses are important and definitive 

elements of both human and non-human animals. With the advancement of science and 

research aimed at understanding the animal world, it is becoming apparent that human and 

non-human animals share a lot of attributes and some misconception of human superiority 

over non-human animals are being challenged and nullified. A worldview that considers 

human and non-human animals as having equal moral considerability is envisaged to bring 

about a better world; built on respect for life. 

 

 

Author Contribution: Both authors contributed equally to the paper. 

 

Conflict of Interest: Declared none. 

 

Acknowledgements: None. 

 

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function_us_5718f789e4b0479c59d7447e. Retrieved on 12 October 2016 


