6.  A Preliminary Evaluation of Two Crucial Premises of Some Central Anti-Abortion Arguments

        The anti-abortion argument schema involves four premises, two of which contain "X" - and which will thus depend upon exactly what is substituted for "X" - and two of which do not.  We have already considered the latter two premises, and we found that while the premise advanced at step (2) seems unobjectionable, the same is not true for the premise advanced at (6).  The latter premise needs to be revised, and this in turns necessitates changes to the rest of the argument, including important changes to the conclusion, since the reformulated conclusion no longer supports an extreme anti-abortionist view.

        Let us turn now to a preliminary evaluation of the two premises that contain the term "X", and let us consider how plausible they appear at first view, under different interpretations.  The idea is simply to try to decide which versions of the central anti-abortion argument are most promising, and so most worthy of closer examination.
 

6.1   A Table for Evaluating Two Crucial Premises of the Central Anti-Abortion Arguments

        The two premises that depend upon what is substituted for the term "X" are expressed by statements (1) and (4):

                (l)  All innocent Xs have a serious right to life.

                (4)  Any human fetus, embryo, or zygote is itself an innocent X.

        To have a sound anti-abortion argument of the type we are considering here, both statement (1) and statement (4) must be true.  What are the prospects for this, under the different possible interpretations?

        Let us consider the following five, representative interpretations:

Interpretation 1:     "a member of the biologically defined species, Homo sapiens"

Interpretation 2:     "an individual with the present capacity for thought and  self-consciousness"

Interpretation 3:     "an organism that has the potential to acquire the capacity for thought and self-consciousness"

Interpretation 4:     "an organism that belongs to a species, normal members of which have the potential to acquire
                                   the capacity for thought and  self-consciousness"

Interpretation 5:    "an organism that possesses an immaterial, immortal soul"
 
 

Table for a Preliminary Evaluation

Interpretation of the Term "X"?         Plausibility of Statement (1)?         Plausibility of Statement (4)?

Interpretation 1                                                                                                                                            

Interpretation 2                                                                                                                                             

Interpretation 3                                                                                                                                             

Interpretation 4                                                                                                                                              

Interpretation 5                                                                                                                                                 
 
 

*********************************************************************************************
 

6.2  Initial Plausibility of the Argument Under Interpretation (1)?

        How plausible are the premises expressed by statements (1) and (4) in the version of the basic anti-abortion argument that results when the term "X" is replaced by the expression "a member of the biologically defined species, Homo sapiens"?

The Premise Expressed by Statement (1)?

        This premise now reads:

All innocent members of the biologically defined species, Homo sapiens, have a serious right to life.

        A liberal on abortion might well want to question this contention, but, initially, it seems fair to say that most people would view it as quite plausible.

The Premise Expressed by Statement (4)?

        This premise now reads:

Any human fetus, embryo, or zygote is itself an innocent member of the biologically defined species, Homo sapiens.

        Though this premise can be questioned, it is surely initially very plausible.  (Some people would argue that although a human fetus, embryo, or zygote is biologically human, it is not a member of the species, Homo sapiens, any more than a single, isolated, human cell is.  It seems to me very doubtful, however, that that objection can be sustained.)
 

6.3  Initial Plausibility of the Argument Under Interpretation (2)?

        How plausible are the premises expressed by statements (1) and (4) in the version of the basic anti-abortion argument that results when the term "X" is replaced by the expression "an individual with the present capacity for thought and self-consciousness"?

The Premise Expressed by Statement (1)?

        This premise now reads:

All innocent individuals with the present capacity for thought and self-consciousness have a serious right to life.

        This can be questioned, but most people would, I think, find it plausible.  (To test one's intuitions about this claim, consider the case of an intelligent extraterrestrial, such as ET.)

The Premise Expressed by Statement (4)?

        This premise now reads:

Any human fetus, embryo, or zygote is itself an innocent individual with the present capacity for thought and self-consciousness.

        This premise, by contrast, seems very implausible indeed.  In the first place, there is no behavioral evidence that a human zygote or embryo (and, many would add, a fetus) has the present capacity for thought and self-consciousness.  In the second place, there is enormous evidence, both in the form of detailed neurophysiological studies of the brain, and in the form of ordinary, everyday knowledge of the effects that injuries to the brain due to accidents or strokes have upon higher mental functions - such as thinking - all of which strongly support the claim that the ability to think not merely depends upon the brain, but depends upon the presence of certain very complex and delicate neurological networks.  It is therefore extremely unlikely that a capacity for thought is present when the brain is just beginning to develop, let alone when - as  in the case of the zygote, and other very early developmental stages - no brain is present at all.
 

6.4  Initial Plausibility of the Argument Under Interpretation (3)?

        How plausible are the premises expressed by statements (1) and (4) in the version of the basic anti-abortion argument that results when the term "X" is replaced by the expression "an organism that has the potential to acquire the capacity for thought and self-consciousness"?

The Premise Expressed by Statement (1)?

        This premise now reads:

All innocent organisms that have the potential to acquire the capacity for thought and self-consciousness have a serious right to life.

        This claim is, I suggest, hard to evaluate.  In the first place, it is, in the case of many people, a claim that they have not encountered before.  In the second place, the claim is also one about which thoughtful ethical theorists disagree.  So it would seem that one will need to take a very close look at arguments for and against it before one is justified in arriving at a confident opinion.

The Premise Expressed by Statement (4)?

        This premise now reads:

Any human fetus, embryo, or zygote is itself an innocent organism that has the potential to acquire the capacity for thought and self-consciousness.

        This claim, by contrast, appears to be false as it stands.  The reason is that there are human fetuses that are anencephalic - that is, that have no brain at all, or virtually no brain.  Given what is known about the dependence of mental functioning - including mental functioning of the most rudimentary kind - upon the brain, it is surely plausible to hold that an anencephalic fetus does not have the potentiality for thought and self-consciousness.
 

6.5  Initial Plausibility of the Argument Under Interpretation (4)?

        How plausible are the premises expressed by statements (1) and (4) in the version of the basic anti-abortion argument that results when the term "X" is replaced by the expression "an organism that belongs to a species, normal members of which have the potential to acquire the capacity for thought and self-consciousness"?

The Premise Expressed by Statement (1)?

        This premise now reads:

All innocent organisms that belong to a species, normal members of which have the potential to acquire the capacity for thought and self-consciousness have a serious right to life.

        This premise is rather similar to the corresponding premise under interpretation 1.  Once again, a liberal on abortion might well want to question it, but most people, I think, would find it initially fairly plausible.

The Premise Expressed by Statement (4)?

        This premise now reads:

Any human fetus, embryo, or zygote is itself an innocent organism that belongs to a species, normal members of which have the potential to acquire the capacity for thought and self-consciousness.

        This premise is, I suggest, quite plausible, though it could be challenged in the same way that the corresponding premise under interpretation 1 can be challenged.  (Here the thrust of the objection would be that not all human cells, or collections of human cells, are properly characterized as organisms belonging to a species.)
 

6.6  Initial Plausibility of the Argument Under Interpretation (5)?

        How plausible are the premises expressed by statements (1) and (4) in the version of the basic anti-abortion argument that results when the term "X" is replaced by the expression "an organism that possesses an immaterial, immortal soul"?

The Premise Expressed by Statement (1)?

        This premise now reads:

All innocent organisms that possess an immaterial, immortal soul have a serious right to life.

        How plausible this is depends on how the term "soul" is being used here.  But if the term "soul" is understood as meaning a substance that contains the basis for the capacity for thought, then I think that most people would find this premise very plausible.

The Premise Expressed by Statement (4)?

        This premise now reads:

Any human fetus, embryo, or zygote is itself an innocent organism that possesses an immaterial, immortal soul.

        This other premise, by contrast, seems very dubious.  For, in the first place, there is no plausible argument or evidence for the presence of an immaterial soul in the case of adult human beings, let alone in the case of zygotes, embryos, and fetuses.  In the second place, and as mentioned above, there is enormous evidence, both from ordinary experience of the effects of injuries to the brain, and from detailed neurophysiological studies of, and experiments upon, the brain, that very strongly supports the conclusion that the ability to think depends upon the presence of certain very complex and delicate neurological structures, and this in turn makes it very unlikely that mental functioning is based upon capacities that reside in an immaterial substance, since, if that were so, there would be no reason at all why one would expect such capacities to be impaired in any way by damage to the brain.
 

6.7  Summing Up:  Which Arguments Are Initially Promising?

        In the light of this preliminary examination, which of the five arguments are at least somewhat promising, and which are not?  The arguments that result from interpretations 1 and 4 - what one might refer to as the biological, and quasi-biological interpretations - certainly appear to deserve a very close look, since, in each case, both premises appear, initially, either very plausible, or at least reasonably so.  By contrast, the arguments based on interpretations 2 and 5 - which appeal, respectively, to capacities, or to an immaterial soul - appear very unpromising, since there is very strong evidence that a capacity for thought is not present until a brain is both present, and sufficiently developed.  Finally, what about the argument based upon interpretation 3 - which involves an appeal to potentialities?  Initially, it might seem that that argument can also be set aside, since the claim that all human zygotes, embryos, and fetuses have the potentiality for acquiring the capacity for thought and self-consciousness is exposed to clear-cut counterexamples in the form of fetuses that are  anencephalic, or that have extremely defective brains.  Nevertheless, it would be a mistake not to consider this line of argument, since even though the counterexamples show that the potentialities version of the central anti-abortion argument cannot support an extreme anti-abortion position, such an argument might support a position that was very close to an extreme anti-abortion position - namely, a position that maintained that abortion was in itself prima facie very seriously wrong except in the case of anencephalic, or very severely brain damaged, fetuses.