When does human personhood begin?

A philosophical analysis challenges the pro-choice position,
writes Prof. William Reville.

Conception is the start of a continuum of an individual human life that ends eventually in death. Under normal circumstances the unfolding along the biological continuum is automatic and self regulating

Some of the various successive stages along the continuum are termed – zygote – embryo – foetus – baby – child – teenager – adult – elderly person. The transitions between these stages are gradual and smooth – there are no sharp lines of demarcation. The human continuum is qualitatively very different from the sperm and egg cells that precede it and the corpse that succeeds it.

The developing entity is unambiguously alive and biologically and genetically Homo sapiens from the moment of conception and at every point along the continuum it has the human properties characteristic of and appropriate to that stage. The full human essence is present everywhere along the continuum.  The full human genetic instructions are already present in the zygote and these instructions play out, in interaction with the environment, to guide development along the human continuum. The foregoing facts convince me that this human continuum is special enough, even at its earliest stages, to merit sufficient respect that it not be deliberately killed, but not everyone agrees with me with this.

There is universal agreement that it is morally wrong to deliberately kill a human anywhere along the human continuum after the baby stage. The reason for this concensus is that everybody agrees that beyond the baby stage of the continuum you are dealing with a human person and civilised standards everywhere label and condemn the deliberate killing of a person as homicide. But many people sincerely believe that personhood does not exist before birth and consequently that killing an embryo or early stage foetus under circumstances where continuing the pregnancy would cause serious distress to the mother, is permissible and is certainly not homicide.

Personhood is typically thought of as the capacity to do various things that are characteristically human – think, know, feel, remember the past, anticipate the future, etc. Obviously the zygote and the early embryo cannot do these things – these behaviours automatically arise later along the continuum. The pro-choice argument is that at the earlier stages of development in the womb, although the foetus is undoubtedly alive and biologically human, it cannot feel physical pain and is not yet a person.

At first glance this seems to be a substantial argument in favour of the pro-choice position but I believe that it fails under philosophical analysis. I am persuaded by the analysis of this position put forward by the American Catholic theologian and philosopher Peter Kreeft. Kreeft claims that the personhood argument is based on functionalism and confuses being with doing. He argues that personhood is present everywhere along the human continuum, beginning with the zygote.

The pro-choice position views the early embryo and foetus as a potential person but not yet an actual person. Personhood is defined as the ability to do certain things as itemised earlier. But if the foetus is only a potential person, what is it actually? Kreeft says the foetus is a person because the proper definition of something is a definition of its essence, not a description of its behaviour. Being is actual, functioning is potential. Potential refers to behaviour and not essence. Thus, according to Kreeft’s analysis, a zygote or a foetus is a person who is a potential musician, swimmer, singer, etc. (Human Personhood Begins at Conception by P. Kreeft, Medical Ethics Monograph, Castello Institute, Virginia, USA).

Functionalism claims that some human beings are not persons because the quality/capacity of their behaviour is not ‘sufficient’ to qualify them as persons. This is a dangerous philosophy. Who decides what is ‘sufficient’? Obviously the decision is made by the stronger and, human nature being what it is, nature, reason and justice can be replaced by artifice, prejudice and power. When it is in the self-interest of powerful people to kill other people, whether they be foetuses, heretics, ethnic groups, or whatever, they can simply define their victims as non-persons because they do not meet certain criteria.

Functionalism is seeping throughout modern society. People are defined more and more by what they do, not what they are. We are bombarded with reports and statistics that speak of engineers, teachers, nurses etc, not men and women who design and build bridges, teach students and nurse patients. This trend is exacerbated by the decline of the institution of the family. The family is the only social institution where you are valued for what you are rather than what you do but, in the developed world, half of all traditional families based on marriage run onto the rocks of divorce. The family, where we are valued for our being, is being replaced by the workplace, where we are valued for our function. Functionalism encourages modern society to replace the traditional ethic of ‘the sanctity of life’ with the ethic of ‘the quality of life’. This already has big implications for both ends of the human continuum – abortion and euthanasia. But who is to decide when the quality of a life is so low that the life is no longer worth living and where have we heard that chilling phrase “lives not worth living” before?

So, in summary, the individual human person begins suddenly at conception, ends suddenly at death and in between gradually develops his/her personal behaviours. The early embryo is a person with potential not a potential person.

William Reville is an Emeritus Professor of Biochemistry and Public Awareness of Science Officer at UCC. http://understandingscience.ucc.ie