abortion
PERSONS
the central argument
The fetus is a person.
2. If (1), the fetus has a right to life.
3. If the fetus has a right to life, abortion is prima facie
wrong.
4. [So] Abortion is prima facie wrong.
1.
persons
persons
persons
the species criterion
 The Species Criterion: Something is a person iff it is a
homo sapien.
commonsense personhood
The characteristics that come at least implicitly to mind
when we hear or use such words as ‘person’, ‘people’, and
the personal pronouns. (F&L, p.201)
the modified species criterion
 The Modified Species Criterion: Something is a person iff
it is a member of a species generally characterized by C
the modified species criterion
The major difficulty… is that it requires further explanation
why C should determine moral personhood when applied
to classes of creatures rather than to individual cases…
Just because opposable thumbs are a characteristic of
Homo sapiens, it does not follow that this or that
particular Homo sapiens has opposable thumbs. There
appears to be no reason for regarding right-possession
any differently, in this regard, from thumb-possession.
(F&L, p.205)
the potential possession criterion
 The Potential Possession Criterion: Something is a
person iff it either actually or potentially possess C.
the potential possession criterion
It is a logical error, some have charged, to deduce actual
rights from merely potential (but not yet actual)
qualification for those rights. What follows from potential
qualification, it is said, is potential, not actual, rights… “A
potential president of the United States is not on that
account Commander-and-Chief.” (F&L, p.206)
the potential possession criterion
Potential possession of C confers not a right, but only a
claim, to life, but that claim keeps growing stronger,
requiring ever stronger reasons to override it, until that
point when C is actually possessed, by which time it has
become a full right to life. (F&L, p.207)
the actual possession criterion
 The Actual Possession Criterion: Something is a person iff
it actually possesses C.
summary
 The Species Criterion
 The Modified Species Criterion
 The Actual Possession Criterion
 The Strict Potentiality Criterion