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May 2015 Policy Study, Number 15-4


Embryonic Stem Cell Research Is Morally Wrong


Section I



This section unpacks the metaphysical foundation for the missing link in Werner’s argument. There are different ways one may interpret personhood. Werner’s argument presupposes that certain properties are supposed to tell us whether someone is a person. Consider the following questions: 1) what are properties; 2) how does one explain personhood in terms of properties; and 3) what is the basis for rights? 


First, properties are the qualities that one says of a thing.  If you say a person is rotund or that grass is green, then you are saying these are qualities of those things. One can think of scores of examples of properties like the greenness, roundness, or grumpiness in things. Greenness can be in the grass. Grumpiness can be in a person. Realize that although a person may be grumpy, a person cannot be grumpiness, nor can grumpy be a person (unless this is his name, like it was of the dwarf).


Werner’s view of personhood implies that a person is only a property-thing. This view says a person arises from the correct combination of certain properties. A property-thing can be illustrated using the example of Lincoln logs. Many of us had Lincoln logs to play with growing up. When describing what kind of fort I built with these Lincoln logs, I’d say it was big, brown, and square, along with some other elements necessary for an adequate abode for my army guys. Perhaps I’d also add some other descriptive terms to help you recreate it. Taking these into consideration, if you were to combine the properties I described, those thinking that anything is simply a property-thing would say you’d have the exact fort I built if you simply recreated those properties. There would be an exact identity between what I built and what you’d built. The reason for this is that there is nothing underneath those properties holding them together (which is what was classically called substance). All things simply are the combination of the different properties, but there is nothing underlying the properties holding these together.


Now consider a person. Rationality, self-awareness, consciousness, language use, and sentience are the properties people exhibit.[2] Rationality and sentience are the essential properties of a person, and the others arise from these essential ones.


According to this account, when certain properties come together a person arises. This is why Werner says one may be a human being and not be a person. Additionally, these properties are what give rise to a person’s value. A human being is not valuable until they exhibit certain properties. The essence of a person is simply the aggregation of these properties, and they accidentally relate to the human body.  When the properties cease functioning through the body, the body loses its value. Thus, the missing link (or unstated assumption) in Werner’s argument is that persons are mere property-things.


Another requirement in Werner’s view of personhood is that for one to be a human person one must have a brain.[3] Because both a brain-dead human and an embryo have no brain, they are not persons. An embryo and a brain-dead human may be human beings, but they are not human persons.[4] For Werner, the basis for our rights is whether or not we are persons.[5] This is why Werner writes that although both a brain-dead human and an embryo are human beings, the embryo “is not yet a fully fledged person, just as the brain-dead human is no longer a fully fledged person.”[6] In order for one to be a fully fledged human person, with all the rights associated with human persons, one must have a brain. A brain is a necessary, but not sufficient condition for personhood.


Further, Werner thinks rationality is the basis for human rights and human personhood. Werner explains, “Personhood is a philosophical concept with moral implications because persons, unlike all members of the species of Homo sapiens, can be harmed.”[7] [Emphasis mine.] Rationality is that which makes a brain-dead human being and an embryo different from a fully fledged human person. Because rationality is the sine qua non for personhood, other species like aliens from other planets can be persons if they are rational.[8] Further, humans who do not act rationally are not persons.[9] Thus, one can be biologically human and still not be a person. The Homo sapiens who are not persons include babies, infants, and humans with severe mental problems (like acute retardation and insanity).[10]


Moreover, for Werner, a person is a being that functions rationally. Remember that in this account only the function of certain human beings makes them valuable. Only persons function rationally. The value of persons entitles them to moral protection. If they do not function rationally, they have no moral protection nor can one harm them because they are not persons.




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