Some arguments in defense of abortion are more intellectually credible than others.
These are not the arguments offered by spokespersons for Planned Parenthood. They aren't the ones offered by media commentators. They certainly aren't offered by political leaders.
They are offered, rather, by moral philosophers and bioethicists. How do these more sophisticated (if not exactly rhetorically influential) arguments hold up to scrutiny?
The function view
Philosophers who defend abortion generally acknowledge that human embryos and fetuses are living individuals of the species Homo sapiens. That's a fact of biology. They typically argue, though, that such human beings are not "persons" with a right to life. To be a person or to have rights, they contend, one must have certain developed mental capacities—functions that (at least many) unborn humans lack.
Call this the function view.
What abilities does the function view deem necessary? Different thinkers propose different criteria. Philosopher Mary Anne Warren proposes five capacities: consciousness (especially the ability to feel pain), reasoning, self-motivated activity, communication, and self-awareness. Only individuals who have at least some of these abilities, she argues, count as persons.
Many of the leading thinkers who support abortion (e.g., Michael Tooley, David Boonin, Bonnie Steinbock) connect rights to desires. An individual can only have rights if she (in some sense) desires, values, or takes an "interest" in her life or future—if it matters to her. And such a desire requires some kind of consciousness or self-awareness.
If a human being has no higher mental functioning, then she can't want or take an interest in anything. Her life doesn't matter to her. And so she has no rights, and killing her is permissible. That's the argument.
Does it work?
The function view's exclusion problem
The function view, in all of its forms, suffers from some serious difficulties.
First, functional criteria for personhood exclude more human beings than just the unborn. If the capacity for consciousness confers personhood, for example, then patients in temporary comas are excluded. If self-awareness or rationality is necessary, then people who are comatose, people with advanced dementia, and people with severe mental disabilities may have no rights.
Suppose that the ability to experience pain grants someone a right to life. In that case, people with a condition known as congenital insensitivity to pain may be killed. Suppose that desires make the difference. In that case, if a Buddhist master succeeds in purging himself of all desire, then killing him is permissible, as philosopher Christopher Kaczor writes.
Human infants pose a massive problem for the function view. Infants are not self-aware. They can't reason or use language. They don't have desires in any robust sense. They don't meet most ordinary functional criteria.
Indeed, in an article for the prestigious Journal of Medical Ethics, Alberto Giubilini and Francesca Minerva argue that killing infants is permissible because newborn children, like unborn children, cannot value their own existence. This conclusion is far from new or unusual. A number of the most prominent thinkers who defend abortion, such as Michael Tooley and Peter Singer, also defend infanticide.
If a view logically entails that it's okay to kill temporarily comatose patients, or Buddhist masters, or infants, then something is deeply wrong with that view.
The function view's inequality problem
A second difficulty is that functional criteria are a matter of degree. People can be more self-aware (e.g., a wise sage) or less self-aware (a man with Alzheimer's disease). They can be more sentient (the heavily caffeinated) or less sentient (the heavily medicated). They can be more rational (Mr. Spock) or less rational (Mr. T). They can have a stronger desire to live (the exuberant and happy) or a weaker desire to live (the dour and depressed). No two people are exactly equal.
If the right to life is based on those degreed characteristics, as the function view claims, then some people have a greater right to life and some people have a lesser right to life. It's not just that the unborn aren't equal to the rest of us—it's that none of us are equal. Our value is measured on a sliding scale. Equality doesn't exist.
"It is hard to avoid the sense that our egalitarian commitments rest on distressingly insecure foundations," acknowledges philosopher Jeff McMahan, a defender of abortion. McMahan worries about "the compatibility of our all-or-nothing egalitarian beliefs with the fact that the properties on which our moral status appears to supervene are all matters of degree."
Some people try to solve the inequality problem by proposing a "threshold" (a certain degree of the relevant trait) and asserting that everyone above the threshold matters equally. Mere assertion, however, doesn't make it true. If the value-conferring trait comes in varying degrees, then any threshold is arbitrary—and actual equality is still a myth.
Where the argument goes wrong
The function view, then, has awful and false implications. That's because it flows from false assumptions.
The most common versions of the view (those that emphasize self-awareness, sentience, and desire) seem to assume that psychological states are all that matter morally—so killing is only wrong if it thwarts someone's desires or conscious experiences. "In order for a harm to occur," explain Giubilini and Minerva, "it is necessary that someone is in the condition of experiencing that harm."
This thinking, however, "confuses the experience of harm with the reality of harm," as ethicist Scott B. Rae observes. Imagine that a man is secretly robbed of an inheritance he never knew he had coming (to use an example from philosopher Robert N. Wennberg). Has he been wronged—even though he doesn't know it? Of course he has. The same is true when someone is robbed of his life.
The primary injustice of killing an innocent human being is not that it thwarts desires he happens to have (though thwarting desires may be, in general, a wrong thing to do). It's that it deprives him of his life. That life is valuable whether he currently values it or takes an "interest" in it or not.
"[I]t is the loss of the good of life, not the interference with the desire for that good, that constitutes the harm [of killing] and hence the wrong done," concludes Kaczor.
We matter because of what we are, not what we can do
The function view is right, however, to think there's something special about the functions typical mature human beings can perform. We can reason, and create, and choose, and love. But the function view is wrong to suppose that having rights requires the present ability to do these things. That idea leads to the injustice and inequality described above.
Indeed, the function view, as philosopher Stephen Schwarz explains, falsely equates functioning as a person with being a person. All human beings have the inherent (or basic) capacity to function in personal ways, whether or not that capacity is developed or currently exercisable. We have this capacity by nature—by virtue of what (i.e., the kind of being) we are.
Actual functioning, then, isn't what matters. We have dignity and a right to life not because of what we can do, but because of what we are. There's no test of mental ability we must pass in order to count.
This is why every single member of the human family has human rights. Infants are included, and comatose patients are included, and people with dementia are included.
This is why we are all equal—because the basis for our value is something we share in common. We are equally human, even though we differ with regard to every function.
And this is why the very best arguments for abortion just don't work, and never will. Because if all human beings have an equal right to life, then so do unborn children.
This article appears in the April 2018 issue of NRL News.