How would you react if you were discussing Earth Hour, and the person next to you claimed that she turned off her lights because all living beings have a good of their own? Amongst others, one question you might have asked is if she really meant absolutely all creatures, even microorganism, bacteria, and mosquitos? For most people the intuitive response to this idea is that the statement is absurd. Several philosophers agree and argue that only humans or conscious beings should be said to possess intrinsic value.
Aristotle and Aquinas
The Greek philosopher Aristotle stated that “nature has made all things specifically for the sake of man”, implying that all non-human beings have a value only by being beneficial to us (Brennan, Andrew, Yeuk-Sze Lo 2008). A similar view can be found with Thomas Aquinas who argued that, “accordingly intellectual creatures are ruled by God, as though he cared for them for their own sake, while other creatures are ruled as being directed to rational creatures” (Aquinas 2002:63). In other words, whereas humans are ruled by God and have a value in themselves, all other living beings are ruled by rational creatures i.e. humans, and have value only by serving our purposes.
Immanuel Kant
The well-known German philosopher Immanuel Kant also argued that only human beings have a value in themselves. This argument was based on the assumption that no other living beings are self-conscious, a trait that is needed to possess intrinsic value (Kant 1995:82).
As an implication he suggests that to act cruelly towards a dog, blinding it, hitting it etc., is wrong, but not because the dog has a value in itself. The wrong lies in the possibility that it might encourage a person to develop a character which would be desensitized to cruelty towards humans (Brennan, Andrew, Yeuk-Sze Lo 2008).
Peter Singer
Other arguments found within philosophy are those that claim intrinsic value is reserved for those possessing consciousness. Peter Singer advocates such a view, attributing intrinsic value to the experience of pleasure or satisfaction of interests as such, and not to the beings who have the experience. Thus, if a living being has the ability to feel pleasure or pain it has a good of its own and moral worth
(Singer 1995, Brennan, Andrew, Yeuk-Sze Lo 2008).
Biocentrists
Biocentrists, however, disagree and argue that all living beings have intrinsic value, including everything from humans and large animals, to plants and teeny microorganisms. This implies that none of the traits emphasised by the philosophers above are necessary conditions for a living being to have a value in itself. The trait needed for possessing intrinsic value and moral worth is nothing short of being alive (Goodpaster 1978).
James Sterba is one of those who not only advocates that all living- beings possess moral worth, but that they have an equal amount of moral worth, also referred to as a biocentric egalitarianism. He bases his justification of this argument on the consideration of how living beings can be benefitted and harmed, and the constraints opposed on us when interacting with them.
The equality aspect may seem even stranger than just stating that everyone has moral worth, does he really mean that a carrot and a human being are equal? For a presentation of what arguments Sterba uses to explain this idea, look under the heading A hierarchy between species? .
References
- Aquinas, Thomas 2002 “Humans as Moral Ends” In David Schimdtz and Elizabeth Willott eds., Environmental Ethics: What really Matters, What really Works Oxford University Press 2002
- Brennan, Andrew, Yeuk-Sze Lo 2008. . “Environmental Ethics” Available at Standford Encyclopedia of Philosophy
- Goodpaster Kenneth E. 1978, «On Being Morally Considerable » New York: The Journal of Philosophy, Vol. 75, No. 6
- Kant, Immanuel 1995 “Indirect Duties to Nonhumans” In David Schimdtz and Elizabeth Willott eds., Environmental Ethics: What really Matters, What really Works Oxford University Press 2002
- Singer, Peter. 1995. Animal Liberation. London : Pimlico
Pictures
- Brothers: Adam Sundana, (CC BY-SA 2.0)
- Plato and Aristotle: Raphael
- Blinded dog: Juan Pedro Diez, (CC BY 2.0)
- Flower: Pixabay, (CC0 1.0)
Environmental ethics 
